# Maintaining a healthy Biofilm



## 13razorbackfan (Sep 28, 2011)

_*Mod Edit:* This discussion about the properties of the biofilm developed from another thread. I spilt it off, because I thought it deserved a wider audience than it would get being buried at the end of another thread. The OP is addressing Dr Tim:_

I am sure you are busy but it would be nice to see a post from you every now and then in regards to nitrifying bacteria and biofilm. In a recent thread I posted/linked to some of your peer reviewed studies and had a quick question.

In canister filters or any filters for that matter is it a good idea to clean the bio media(ceramic rings in my case) every so often as to keep the gunk from building up too much thus suffocating the nitrifying with other types of bad(what we would consider bad in this hobby) bacteria? I was reading a post you made on another forum in regards to the bio wheel design by marineland. You mentioned it was a good design because it keeps the biofilm clean of buildup. So I took that to mean it is a good idea to keep other bio media clean of gunk as well. I have been cleaning my bio media in old tank water or dechlorinated water as soon as I notice any build up. I don't scrub or even clean it vigorously but gently dip it in the water until it is clean/er.

Your thoughts?


----------



## DrTim's (Jun 8, 2010)

I will try to post on a more regular basis some things that might be interesting but you can always pose a question and I will respond.

I am not, and never have been, a believer in doing nitrification in a sealed canister filter and have also always believed that the mechanical and biological filters should be separated - hence the biowheel.

A great illustration of why is provided in the image below. This is not my work (wish it was!) But using microelectrodes these researchers showed that the zone of nitrification in a biofilm is ONLY around 100 micron thick - that's microns - very very small. In the image it is the black area with the blue area the water above the nitrifying bacteria zone.

If you add a layer of gunk on top of the nitrifying zone you won't get oxygen to the nitrifying zone and the process will not work.

This is why keeping the biofilm thin is the best course of action along with not letting it get buried with gunk. The nitrifier biofilm is also pretty sticky so what you are doing by gently dunking but not scrubbing the media is the right thing to do. Plus there is not reason to get the gunk in the tank - trap it and remove it. So I agree with what you doing.

Cheers

DrTim


----------



## 13razorbackfan (Sep 28, 2011)

Awesome....that is the same link(the pic you posted above) that I posted in another thread. I used the pic above and your brief description to come to my conclusion. I am glad to hear that I am going about it right. I do have holey rock in my aquarium along with very good surface agitation and overall circulation. I believe the holey rock with it being fairly porous and many holes adds something in the nitrification process. I did have bio-wheels on my tank but took them off recently in lieu of canister filters. I am hoping with the very strong circulation and gas exchange I have in my aquarium that the bacteria I do have is getting plenty of oxygen in order to reproduce and multiply. I hope that plus the cleaning of the ceramic rings I am using will act or do some of the same things the bio wheels were doing.

One more quick question and I will leave you be....

How sensitive is the bio film to small amounts(my tap water I believe is around 1.45ppm) of chlorine? Meaning how quickly will the chlorine attack and kill the bacteria and the bio film? I guess what I am getting at is the way I fill my tank during water changes. I fill the tank and add the dechlorinator at the same time but it still needs to mix and neutralize before it hits my beneficial bacteria. Some people claim to wash their media in tap water with no ill effects. What are your thoughts?


----------



## DrTim's (Jun 8, 2010)

You always want to be careful with chlorinated water but the biofilm does provide a good layer of protection for the nitrifying bacteria. This is actually a major problem for water distribution companies because they have found that they have to add even more chlorine/chloramine to the water to disinfect it because the biofilm of nitrifiers on the inside of the pipes are quite resistant to the 'normal' chlorine levels.

A quick wash/rinse will not hurt the nitrifiers. If you add add the chlorinated water directly to the tank with fish in the tank I would be more worried about the fish than the bacteria.


----------



## 13razorbackfan (Sep 28, 2011)

DrTim's said:


> You always want to be careful with chlorinated water but the biofilm does provide a good layer of protection for the nitrifying bacteria. This is actually a major problem for water distribution companies because they have found that they have to add even more chlorine/chloramine to the water to disinfect it because the biofilm of nitrifiers on the inside of the pipes are quite resistant to the 'normal' chlorine levels.
> 
> A quick wash/rinse will not hurt the nitrifiers. If you add add the chlorinated water directly to the tank with fish in the tank I would be more worried about the fish than the bacteria.


I feel like I am back in school.....I love this stuff. There is a huge difference between information gathered from other users who have been told x, y and z versus a reputable source of knowledge such as yourself. I am soaking this stuff up.

Just so you know...I appreciate your time and willingness to answer my questions. Thanks again...


----------



## 13razorbackfan (Sep 28, 2011)

Thanks for the move fmueller....

Anybody else have any questions or thoughts on this subject? This is the guy to ask so ask now or forever hold your peace......


----------



## fmueller (Jan 11, 2004)

DrTim's said:


> I am not, and never have been, a believer in doing nitrification in a sealed canister filter and have also always believed that the mechanical and biological filters should be separated - hence the biowheel.


I can see Dr Tim's point that the bacteria might be happier on a biowheel than in a sealed canister. But for me the bacteria are just a means to an end - I am mostly interested in fish and a good looking setup. I am not a huge fan of biowheels, because I don't like HOB filters. To me they are noisy eye sores that mostly pump around water for the sole reason of boosting a gph value, which can be used in marketing.

Of course providing an abundance of oxygen to the nitrifying bacteria is crucial for successful biological filtration, but I believe oxygen has additional benefits in an aquarium beyond sustaining the bacteria. I don't have the scientific data to back this up, but in my experience fish are healthier in tanks with oxygen at saturation levels. That's why I believe it's worth the effort to get oxygen into the water rather than exposing bacteria to atmospheric oxygen.

There are many ways to keep oxygen at saturation levels. Any air driven sponge filter will do it, as will a Durso Standpipe in tanks with a sump system. In tanks with a canister filter I have severe doubts about submerged spray bars which simply ripple the water surface. A spray bar above the water surface will do it, but I prefer a venturi valve in form of an Eheim diffusor for various reasons. If oxygen is at saturation levels, I think nitrification works well enough in a sealed canister, and besides the filter media there are many surface areas in my planted and heavily decorated tanks that bacteria can and will settle on.





_Eheim diffusor in action in a 125G Tropheus tank._


----------



## 13razorbackfan (Sep 28, 2011)

^^^^I totally agree. I have very good surface disturbance and an over abundance of GPH to make sure my water stays very well oxygenated.


----------



## robjohnson (Jun 5, 2012)

Something like this is exactly what I was looking for, thanks for already having answered my question guys. xD


----------



## hawkkerw (Jan 31, 2012)

It has always seemed to me that africans seem to enjoy a good water flow they almost seem to make a game of playing in the filter output. I know that allot of folks don't seem to like it but does not some micro bubbles from the output indicate good oxygen flow in the water. Now, I may have missed this in another thread but is it possible to over filter...meaning not enough ammonia etc. in the water to feed the good bacteria to a point where the cycle is off balance? And again please forgive me if this has already been addressed and I missed it.


----------



## rp-photo (Sep 22, 2011)

gee thanks... now my head hurts...


----------



## 13razorbackfan (Sep 28, 2011)

hawkkerw said:


> It has always seemed to me that africans seem to enjoy a good water flow they almost seem to make a game of playing in the filter output. I know that allot of folks don't seem to like it but does not some micro bubbles from the output indicate good oxygen flow in the water. Now, I may have missed this in another thread but is it possible to over filter...meaning not enough ammonia etc. in the water to feed the good bacteria to a point where the cycle is off balance? And again please forgive me if this has already been addressed and I missed it.


viewtopic.php?f=4&t=246181&start=15

Start there....I will let Dr. Tim tell you in his own words....

HTH


----------



## hawkkerw (Jan 31, 2012)

OK First let me say Duhhh!!!!!!! If I just stopped and read all the post properly I would have answered my own question. I often just scan the subjects as time permits when I should slow down and pay more attention and in this case the thread was right there


----------



## fmueller (Jan 11, 2004)

hawkkerw said:


> It has always seemed to me that africans seem to enjoy a good water flow they almost seem to make a game of playing in the filter output.


That's true for the most commonly kept African cichlids, mbuna. It is also true for tropheus, who fill the same ecological niche in Lake Tanganyika that mbuna fill in Lake Malawi - and hence have very similar behavior. As a generalization for all African cichlids it is not true. Fish like Frontosa and most peacocks are not overly keen on strong currents.



> I know that allot of folks don't seem to like it but does not some micro bubbles from the output indicate good oxygen flow in the water.


I have always wondered what some people's adversion to 'micro bubbles' is about. I think it's a question of aesthetics, and some people simply don't like the look. That micro bubbles are harmful to fish is an urban myth, and I think they are a sign of a healthy tank



> Now, I may have missed this in another thread but is it possible to over filter...meaning not enough ammonia etc. in the water to feed the good bacteria to a point where the cycle is off balance?


I assume the reason 13razorbackfan provided a link to the other thread is that Dr Tim explained there that the bacteria will not die even if they are deprived of ammonia and oxygen when shipped in a bottle. They will simply lie dormant until food is provided again.

More to the point of your question is the fact that ammonia can not be removed by filtration (meaning mechanical filtration). Ammonia forms a homogenous solution in water, meaning it can not be removed by even the finest mechanical filters. The only way it is removed is by biological filtration, that is if bacteria eat it. If more ammonia is provided, the bacteria will divide until there are enough of them to take care of the ammonia. If less ammonia is provided, some bacteria will go dormant (and I guess eventually die off after a long time). At any rate, the biological filtration will always strive to be at a balance, and it does a remarkable job at achieving that!


----------



## hawkkerw (Jan 31, 2012)

Oh and also just in my own defence I have a cognitive disorder which sometime can realy upset me because it causes my attention span to be about the same as cucumber. I realy enjoy the list and if I do sometime post something stupid please forgive me.


----------



## 13razorbackfan (Sep 28, 2011)

hawkkerw said:


> Oh and also just in my own defence I have a cognitive disorder which sometime can realy upset me because it causes my attention span to be about the same as cucumber. I realy enjoy the list and if I do sometime post something stupid please forgive me.


Hey...I am very bad about not reading an entire thread...I just skim most of the time. So you are not the only one who does this. I imagine most people do. There is nothing to apologize for.

Fmueller...to your point about bacteria die off from lack of enough food that is something I was curious about as well. If you find anything be sure to pass it along. I guess an example would be a tank with X amount of bacteria to feed off of X amount of waste. All the sudden the waste load is cut in half for whatever reason(removal of fish, less feedings, etc...) how long before the excess bacteria start to die off or do they start to split the waste(food) more efficiently?


----------



## jd lover (Mar 11, 2011)

13razorbackfan said:


> hawkkerw said:
> 
> 
> > Oh and also just in my own defence I have a cognitive disorder which sometime can realy upset me because it causes my attention span to be about the same as cucumber. I realy enjoy the list and if I do sometime post something stupid please forgive me.
> ...


from what dr tim said yesterday they dont die but simply stops multiplying. that is why his bacteria in a bottle works. still skeptical but atleast he took the time to explains it. by the way GREAT QUESTION on the other thread! this should diffinitely be a sticky


----------



## fmueller (Jan 11, 2004)

13razorbackfan said:


> Fmueller...to your point about bacteria die off from lack of enough food that is something I was curious about as well. If you find anything be sure to pass it along. I guess an example would be a tank with X amount of bacteria to feed off of X amount of waste. All the sudden the waste load is cut in half for whatever reason(removal of fish, less feedings, etc...) how long before the excess bacteria start to die off or do they start to split the waste(food) more efficiently?


Good questions to ask Dr Tim! He might have done work on that already, because this is exactly what would determine the shelf life of his product. If there is an expiration date on One and Only, that's probably your answer.



jd lover said:


> from what dr tim said yesterday they dont die but simply stops multiplying. that is why his bacteria in a bottle works. still skeptical but atleast he took the time to explains it. by the way GREAT QUESTION on the other thread! this should diffinitely be a sticky


Dr Tim said the reason his bacteria survive in the bottle is that they don't die but simply stop multiplying. I am no microbiologist, but I think that's called 'lying dormant'.

Dr Tim didn't say the reason other bacteria don't work is that they die. He said the reason other bacteria don't work is that they are the wrong species. Apparently people have been selling the same nitrifying bacteria that are used in waste water treatment plants for use in aquariums. The achievement of Dr Tim's PhD research was to find out that the waste treatment bacteria are not found in aquariums, and also don't work under the low ammonia conditions we have in aquariums. Dr Tim then identified the nitrifying bacteria that are found in aquariums, and he put those in a bottle - voila, there you have his business idea!

I must say this all sounds very convincing to me. If I was the first person to do research on nitrifying bacteria, I'd look where there are a lot of them! That's what any researcher with half a brain would do. You'd expect a lot of nitrifying bacteria to be where there is a lot of ammonia - so you'd look in the sewer! In water where there is less ammonia, you'd expect to be less of the same bacteria. To find an entirely different type would come as a huge surprise, but of course it's possible. Dr Tim must have shown without a shadow of doubt that the two bacteria species are different, or else he wouldn't have received his PhD - and you'd still get away with putting his Dr tile in quotation marks 

Regarding stickies, few people ever seems to read them, and chances that they are read by some seem to diminish quickly if there is more than one per forum! On the other hand, if anybody feels like writing up an article for the library on this stuff, I'd volunteer to proof read and help to finish it!


----------



## DrTim's (Jun 8, 2010)

fmueller - I agree oxygen is critical for more than the bacteria. After all these are fish tank! How with a canister filter the reality is that more people (I am sure you and all the other members of cichlid-forum are not in this group) only clean their canister filter when water has nearly stopped flowing through it. At this point the filter is clogged, the nitrifiers are toast and the canister filter has ceased to be much use as a biological filter. A properly maintained (cleaned often) canister filter can work well but then again filter that it regularly maintained with work. The problem is most people don't regularly maintain their filters.

As for what happens with the bacteria is there is "not enough" ammonia - the cell process slow. Also all bacteria in a fish tank are subject to predation so they do get eaten - basically the population number changes over time due to a few factors. But when the ammonia increases two things happen - the individual cell can process more ammonia faster and the cell can divide producing more bacteria to take care of the ammonia/nitrite.


----------



## jd lover (Mar 11, 2011)

so basically its like the snails in aquariums? if food is plenty they multiply if not they laid and wait?


----------



## DrTim's (Jun 8, 2010)

yes - that is a pretty good analogy


----------



## fmueller (Jan 11, 2004)

DrTim's said:


> How with a canister filter the reality is that more people (I am sure you and all the other members of cichlid-forum are not in this group) only clean their canister filter when water has nearly stopped flowing through it.


I have to admit that I am a very infrequent canister filter cleaner. I aim for 2-3 times per year. But, I am using large filters (Eheim 2260 on 125G and 2217 on 75G), and I fill them all the way with filter floss, which in my experience makes by far the best use of the filter volume. I also have a very good flow indicator in form of the Eheim diffusor I mentioned earlier. If the flow drops below a certain level, the venturi effect stops working, and that is very obvious even if you just walk by the tank, because there are no bubbles. At that stage there is still a very good flow through the filter. But if that happens, I need to clean the filter immediately, because my fish, being used to high oxygen content, will be gasping for air at the surface within hours.


----------



## 13razorbackfan (Sep 28, 2011)

DrTim's said:


> fmueller - I agree oxygen is critical for more than the bacteria. After all these are fish tank! How with a canister filter the reality is that more people (I am sure you and all the other members of cichlid-forum are not in this group) only clean their canister filter when water has nearly stopped flowing through it. At this point the filter is clogged, the nitrifiers are toast and the canister filter has ceased to be much use as a biological filter. * A properly maintained (cleaned often) canister filter can work well but then again filter that it regularly maintained with work. The problem is most people don't regularly maintain their filters.*
> 
> As for what happens with the bacteria is there is "not enough" ammonia - the cell process slow. Also all bacteria in a fish tank are subject to predation so they do get eaten - basically the population number changes over time due to a few factors. But when the ammonia increases two things happen - the individual cell can process more ammonia faster and the cell can divide producing more bacteria to take care of the ammonia/nitrite.


LOL....I have OCD, quite literally, so cleaning the filters is not an option for me. It happens no matter how much I resist the urge. So I guess this is one time where my disorder is actually beneficial.


----------



## jd lover (Mar 11, 2011)

13razorbackfan said:


> DrTim's said:
> 
> 
> > fmueller - I agree oxygen is critical for more than the bacteria. After all these are fish tank! How with a canister filter the reality is that more people (I am sure you and all the other members of cichlid-forum are not in this group) only clean their canister filter when water has nearly stopped flowing through it. At this point the filter is clogged, the nitrifiers are toast and the canister filter has ceased to be much use as a biological filter. * A properly maintained (cleaned often) canister filter can work well but then again filter that it regularly maintained with work. The problem is most people don't regularly maintain their filters.*
> ...


i know what you mean lol i have a prefilter on my filters and i still HAVE to clean it as often as i have time for lol. just doesnt feel right having my fish in water i wouldnt drink (not saying i drink my tank water or anything.... lol)


----------



## 13razorbackfan (Sep 28, 2011)

jd lover said:


> 13razorbackfan said:
> 
> 
> > DrTim's said:
> ...


You're telling me....I have a pre-filter sponge on my maxi jet 1200 and every water change I take it off and clean it. Then I have to put it back on and re-align the power head so it is straight. Then sometimes when I turn it back on it doesn't come on so I have to stick my hand back in the tank and jiggle it. Don't get me started on my obsession with my AC110. Constantly checking to see if the basket is popping up and constantly making sure the output lever is in the furthest left position. For those reasons I am getting rid of both and getting the FX5 to go with my other canister filter.

I also have a late night checklist routine that I do before I turn the lights out. Don't laugh....I first check the AC110 to make sure the basket hasn't popped up. I then make sure the water is flowing properly. I then check all four of my bulbs to make sure one has not burned out. I then check my tank temp on both thermometers. I then check to make sure my maxi jet is flowing. I then make sure my aquatop canister is flowing. I then make sure my UV lamp is working. I then clean the glass and run the magfloat against the tank trim to remove any sand banks built up by the fish digging. I then do a head count. I do all of this several times a day. Every day.

That is a good day. On bad days I double check the plugins to the wall to make sure everything is plugged in. I check for dust, literally, on the glass lids and tank trim. I also check to make sure no water has gotten in between my glass lids and my tank trim. If so then I take a lint free rag and wipe clean. I could go on and on...but I think you get the point. It gets to be too much at times.


----------



## Guest (Jun 6, 2012)

fmueller said:


> I know that allot of folks don't seem to like it but does not some micro bubbles from the output indicate good oxygen flow in the water.
> 
> I have always wondered what some people's adversion to 'micro bubbles' is about. I think it's a question of aesthetics, and some people simply don't like the look. That micro bubbles are harmful to fish is an urban myth, and I think they are a sign of a healthy tank


let me ask a question about this...

i'm all for micro bubbles because to me personally, it indicates to me that my tank is healthy and my fishes seem to enjoy chasing it around. then there are some people what say micro bubbles are bad because it could potentially kill my fishes. so what is it about micro bubbles that can "kill" my fishes?

to me, doesn't micro bubbles mean that there is actually oxygen flowing throughout my tank and it's a benificial thing for both the tank and fishes?

thanks :thumb:


----------



## nodima (Oct 3, 2002)

fmueller said:


> I have always wondered what some people's adversion to 'micro bubbles' is about. I think it's a question of aesthetics, and some people simply don't like the look. That micro bubbles are harmful to fish is an urban myth, and I think they are a sign of a healthy tank


I am in the no micro bubbles camp. To me, they make the tank look dusty and decidedly not clear. The reflection of light off of the bubbles is not appealing to me.


----------



## DrTim's (Jun 8, 2010)

Since we are on the topic of biofilms I'll toss in that the biofilm is the major difference between my bacterial product and others. Nitrifiers want to stick to something -- when they are free swimming in a solution that is a sign of stress.

The biofilm also helps protect them from drying out and is the first line of defense for the bacteria (yes, bacteria have pests - they'll called viruses [but that's whole other topic]). What we do is grow the nitrifiers on a very small particle so that they are already on a surface when we bottle them. This puts them in a better physiology state and so they can stay more active longer in the bottle.


----------



## Pizzle (May 24, 2011)

Dear Dr. Tim, what does your research suggest about doing a large water change in the middle of a fishless cycle in order to reduce the nitrites? I have read some people on this site, whose opinion I respect very much, that there is a risk of disrupting the cycle if a large water change is done in the middle of cycling. I personally did a 60% to 70% water change during cycling in order to drop the nitrites, which were off the chart of the API kit, and I feel it helped to cycle my tank more quickly. Of course I was careful to match the temperature and I used Amquel to break the chloramines bond. Is it possible to disrupt the cycle by doing a water change during the process of cycling a tank? Thank you.


----------



## prov356 (Sep 20, 2006)

fmueller said:


> I have to admit that I am a very infrequent canister filter cleaner. I aim for 2-3 times per year. But, I am using large filters (Eheim 2260 on 125G and 2217 on 75G), and I fill them all the way with filter floss, which in my experience makes by far the best use of the filter volume.


If I recall, when you clean them you dump all the floss and start fresh. Do you stagger cleanings? Since you don't experience ammonia/nitrite spikes during the complete swap of floss, it does suggest that whatever bio they were doing wasn't significant or there was a dramatic and quick rebound of the bacteria population. I tend to think the former, but can't say for sure. I think the surface area provided by your rock background and the water flow that you mentioned may provide significant bio instead, So, it becomes less important that your Eheim filters do anything more than mechanical. Not saying for sure that they don't, but I can see where with your system, it'd be less important that they do. I've always suspected that if a system had a significant amount of surface area in the aquascaping and good water flow that you could experience enough nitrification that it may be possible to not use plugin filters for bio at all. But, I suspect that system would always be tettering on the edge of disaster, so I'll stick with the filters.

I had an experience recently where I was trying to cycle a tank that just wouldn't. The others that I was working with were progressing right along, but this one seemed at a standstill. Very slow progress. It was one of a row of 2,5's that I hadn't lit yet. One day I finally put a strip LED over the tanks and noticed that the airline had come loose enough that there was no flow up the filter sponge uplift tube. There was my problem. I fixed it and cycling progress normally. So, at least in this case, the tank surface are wasn't getting it done. The surface area in the sponge filter mattered and mattered a lot.


----------



## DrTim's (Jun 8, 2010)

Pizzle - I know from experience that if the ammonia/nitrite are above 5 mg/L-N and you do a large water change the process will kick-in and the tank will cycle relatively fast. I have never had a problem with large water changes.

But I do read about it from people who are not novices and have lots of experience. Since I do not know exactly how they are changing their water I can't tell for sure what the problem is but I can tell you some potential problems that may occur with large water changes:

1) siphon cleaning the substrate during the water change - this is where the bacteria reside and if you clean the substrate you are removing the bacteria. My advice is to not touch the substrate for 4 weeks after starting a new tank.

2) adding *a lot* of Prime or Amquel Plus. I know I may catch some flak for this but my number one question when people call or email me about cycling problems is "are you adding a lot of Prime/Amquel Plus" - 97 out of 100 say yes. If I can get them to stop the process will restart. These products do work to remove chlorine, chloramine and ammonia but at high doses they somehow inhibit the nitrifiers. High dose means when you are adding the product to basically control ammonia/nitrite. So it goes like this - I have high ammonia/nitrite, I going to do a big water change and since I have to add prime/amquel plus to the new water anyways I going to really give it a good shot and pour in 10x the normal dose. A mistake IMO.

3) pouring the water into the tank such that it really stirs up the substrate - this is kind of like number 1 above but the bacteria are still in the tank but they were removed from the substrate and now are being trapped in the filter/sponge. One of two things happens - one) the bacteria are in the water column and are stressed at least for awhile while they settle back down so ammonia/nitrite goes up or two) since the water was cloudy from the process and then clears the aquarist decides its a good time to clean the filter pad/sponge and there go the bacteria down the drain

As for temperature and water hardness - as long as the new water values are near to the tank values I don't see these are a problem.


----------



## fmueller (Jan 11, 2004)

prov356 said:


> If I recall, when you clean them you dump all the floss and start fresh. Do you stagger cleanings?


It's not some thing I recommend as a general practice - certainly not for recently set up tanks - but yes, when I clean the filter I discard the entire floss, which is all the media I have in the filter. On tanks with an Eheim canister, I have no other filter, so I don't stagger filter cleanings, but I wouldn't clean the substrate at the same time. The way they are set up, my tanks need very infrequent substrate cleaning, because any debris is swept into the filters. I never clean my rocks.



prov356 said:


> Since you don't experience ammonia/nitrite spikes during the complete swap of floss, it does suggest that whatever bio they were doing wasn't significant or there was a dramatic and quick rebound of the bacteria population. I tend to think the former, but can't say for sure.


I have thought about this too, and initially came to the same conclusion. However, I have taken the canister of one of my tanks and put it on a newly set up tank - new substrate, new rocks, new water with just dechlor added. I found the tank fully cycled and ready to stock. This supports the theory of a quick rebound. I think if you have a well established tank with bacteria well spread out over the decorations and filter media, if you loose half your stock of bacteria, they will bounce back to 100% in no time. In practice this means if you loose either the bacteria in the tank or in the filter media, it's a non issue. You just don't want to use both at the same time. Again, this is true for tanks that have been running for years and had their ups and downs. Presumably there are plenty of dormant bacteria around which would enable a super fast rebound. A tank that has been set up only a few months ago is a different story altogether.



prov356 said:


> I think the surface area provided by your rock background and the water flow that you mentioned may provide significant bio instead.


The rock background is in my 240G, which has a sump. The Eheims I have on my 125G (2260) and 75G (2217). Those tanks have no rock background. Come to think of it, I swapped the entire decorations in both of those tanks from wood to holey rock about a year ago. Maybe I should be more careful with filter cleanings, but I kept the substrate :lol:



prov356 said:


> I've always suspected that if a system had a significant amount of surface area in the aquascaping and good water flow that you could experience enough nitrification that it may be possible to not use plugin filters for bio at all. But, I suspect that system would always be tettering on the edge of disaster, so I'll stick with the filters.


The rocks you have in some of your tanks are pretty much the equivalent of my rock background. They are just not fixed to the backwall. I agree with what you said, and I too prefer to keep the filters. My 240G has two large pieces of Poret in the sumps as dividers - basically two huge HMFs.



prov356 said:


> I had an experience recently where I was trying to cycle a tank that just wouldn't. The others that I was working with were progressing right along, but this one seemed at a standstill. Very slow progress. It was one of a row of 2,5's that I hadn't lit yet. One day I finally put a strip LED over the tanks and noticed that the airline had come loose enough that there was no flow up the filter sponge uplift tube. There was my problem. I fixed it and cycling progress normally. So, at least in this case, the tank surface are wasn't getting it done. The surface area in the sponge filter mattered and mattered a lot.


Interesting. Could it have been insufficient oxygen in the water due to the airline being loose?


----------



## Ensorcelled (Mar 1, 2011)

fmueller said:


> DrTim's said:
> 
> 
> > I am not, and never have been, a believer in doing nitrification in a sealed canister filter and have also always believed that the mechanical and biological filters should be separated - hence the biowheel.
> ...


Fmueller - This post is incredibly interesting to read and is an eye opener. I have a few questions though regarding your view(s) on oxygen saturation from what posts I've read from you so forth.

So are you suggesting that a tank with a high turnover rate aka Mbuna, overall oxygen saturation will be relatively higher because of the turnover and or surface agitation? If that is true, what would the results of a slower turnover rate tank, aka Fronts/Peacocks assuming there is still plenty of surface agitation?

Secondly, more of a chain question from the above regarding surface agitation. I noticed that you mentioned and use the eheim diffusor (thanks for the great video too!). Within your video I notice that you don't seem to have much surface agitation, yet you do have the Eheim 2260 standalone running only the diffusor. What I am curious about is if your oxygen saturation would be the same or less if you ran the 2260 with a spraybar (no diffusor) for surface agitation and theoretically additional equipment for surface or non-surface agitation (i.e. powerhead pointing up towards the surface or down towards an intake for floating debris)?

I have read your article on your website about 2-3 times over to try to really grasp what you are presenting here. I don't want my questions to seem "challenging" as I am really just trying to get a full understanding on this.


----------



## prov356 (Sep 20, 2006)

> Interesting. Could it have been insufficient oxygen in the water due to the airline being loose?


The bubbling (therefore circulation) was the same. It just wasn't directed through the uplift tube, so there wasn't the flow through the sponge.


----------



## BillD (May 17, 2005)

There have been some interesting opinions as well as facts presented in this thread. I have to agree with Dr. Tim for the most part with regard to cannisters. They are, in fact, used by most aquarists as long term storage for debris, rather than true filters. A biological filter does need to be relatively clean to work efficiently. If you look at wet/dry filters that use bio balls, the water that reaches the balls is filtered to remove solids before it reaches the balls. Some sort of fine filter material is used to catch particles, large and small, and this debris is removed on a regular basis, so the balls stay "clean". In a cannister that is allowed to collect and store debris, until the flow is visibly reduced, the function is severely reduced long before it reaches that point. In fact, as a filter starts to clog, it becomes better as a mechanical filter, at the same time as it's biological efficiency drops. The fact that a cannister is much more of a pain to clean as opposed to say, an AC filter which can be cleaned without turning it off, while doing the weekly water change, so they tend to be left for long periods. It is my estimation that this practice appears to work because as long as there is water movement in the tank, all the solid surfaces that are covered with nitrifying bacteria, are picking up the slack. So, we could say it works in spite of our efforts, not because of them.
It is my belief that the best filtration, is the type YOU are willing to maintain correctly. Anything left in the filter is still in the tank. I can only imagine the outcry if someone were to come on here and say they use UGF, and only clean it once every 6 months. Many cannister filter users do this as regular practice, and even defend the practice. Ultimately, it is up to the user of any filtration as to how well it is allowed to work. For me, a filtration system isn't meant to be a storage device for digestive waste.


----------



## fmueller (Jan 11, 2004)

BillD said:


> There have been some interesting opinions as well as facts presented in this thread.


The only person around here who can credibly claim to present facts is Dr Tim. His observations were made under controlled conditions in a laboratory environment and the results of his work were published in peer reviewed scientific journals. Those results are facts. The rest of us, myself included, make observations in our home aquaria, which can lead to reasonable assumptions at best. Regarding opinions, I guess we all know what Clint Eastwood as Dirty Harry said about them 



BillD said:


> The fact that a cannister is much more of a pain to clean as opposed to say, an AC filter which can be cleaned without turning it off, while doing the weekly water change, so they tend to be left for long periods. It is my estimation that this practice appears to work because as long as there is water movement in the tank, all the solid surfaces that are covered with nitrifying bacteria, are picking up the slack.


The problem with HOB filters, with the exception of a few models like the AC110, is that their media volume is so pathetically small that whatever media you put in there, they could never house enough bacteria for any decent sized tank. In addition, most users can't resist fondling their toys on a daily basis, which isn't exactly conducive for the establishment of a healthy bacteria colony.

Canisters have longer maintenance periods not out of laziness, but by design. It actually helps a bacteria colony to get established if you leave it alone for a while to do its job. The way I run my canister filters - packed all the way with filter floss - the bacteria colony has a chance to move up in the filter as the filter material is used up. With dirty water coming in at the bottom of an Eheim classic series filter, that's where the bacteria will establish themselves first. As this layer catches incoming debris and becomes dirty and mucked up, the bacteria are pushed higher into the filter. This process continues as the layer of dirt in the filter increases. I aim to open and clean the filter just before the dirt reaches the top of the filter floss.

You can actually see that this process is happening in the way I describe by opening the filter at various times, and checking how much of the filter floss is brown. Initially you have a thin brown layer at the bottom, which becomes thicker and thicker until it reaches the top. In my opinion, that's the muck replacing the bacteria.



BillD said:


> It is my belief that the best filtration, is the type YOU are willing to maintain correctly.


Amen to that!



BillD said:


> Anything left in the filter is still in the tank. I can only imagine the outcry if someone were to come on here and say they use UGF, and only clean it once every 6 months. Many cannister filter users do this as regular practice, and even defend the practice. Ultimately, it is up to the user of any filtration as to how well it is allowed to work. For me, a filtration system isn't meant to be a storage device for digestive waste.


The outcry wouldn't come from me! However, I don't know anybody who uses UGFs and cleans them as often as once every 6 months. Keep in mind that a UGF will not be clean after a gravel vacuuming. To get an UGF as clean as a canister, you need to completely dismantle the tank, remove the substrate, and get under the plates. Most people do this never while the tank is in operation.

Another big difference is that oxygenated water circulates through an entire canister filter. Certainly in my canister filters there are no dead spots and there is no anaerobic decomposition going on in there. If it was, I could certainly smell it upon opening the filter. If you have ever broken down a tank that had an UGF installed, you will certainly remember the smell of rotten eggs indicating H2S, the product of anaerobic decomposition.

When I open my canister filters, they contain no plant parts or anything that could be broken down further. The nitrifying bacteria have long ago broken down anything they could digest, and the resulting nitrate has been removed via water changes. If that wasn't so, I could not have nitrate at undetectable levels with tanks that have the filters cleaned only once every 6 months. The debris left in the filter is inert material which does no harm, and I am happy for the filter to store it until I get around to removing it.



Ensorcelled said:


> Fmueller - This post is incredibly interesting to read and is an eye opener. I have a few questions though regarding your view(s) on oxygen saturation from what posts I've read from you so forth.


I should probably explain what I mean with 'oxygen at saturation levels'. Of anything that dissolves in water, you can only dissolve a certain amount in a given quantity of water. Take sugar, for example. If you have a cup of coffee, and you put sugar in it, with two teaspoons of sugar the drink will be sweeter than with one. With three it will still be sweeter, and every time you stir the coffee all the sugar will dissolve. However, if you keep adding more sugar, at some stage you can stir as long as you like, but there will be some sugar lying at the bottom of the cup, and there is no way you can dissolve it. If you now ad more sugar, it will simply ad to the solid residue at the bottom of the cup, but the coffee will not become sweeter. In that water, sugar is at saturation levels, meaning there is as much of it dissolved as possible.

Dissolving oxygen in water works in a similar way. There is only a certain amount of oxygen that can dissolve in water. If you bring the water in which oxygen is constantly being consumed (eg by fish and bacteria) into contact with air, a little oxygen will dissolve. If you move the water so the surface gets rippled, it gets in contact with more air, and more oxygen is dissolved. However, at some stage no amount of more rippling and bubbling will dissolve more oxygen in the water. This means oxygen is at saturation levels - despite the fish and bacteria consuming it, there is as much oxygen in the water as possible.

While the sugar example is a good one, there is one point in which it fails. If you heat up water, you can dissolve more sugar in it than if it is cold. The saturation level for sugar in water is higher at 90F than at 60F, for example. For oxygen the opposite is true, you can dissolve more oxygen in cold water than when it is hot. The reason for that is that sugar is a solid, while oxygen is a gas.



Ensorcelled said:


> So are you suggesting that a tank with a high turnover rate aka Mbuna, overall oxygen saturation will be relatively higher because of the turnover and or surface agitation? If that is true, what would the results of a slower turnover rate tank, aka Fronts/Peacocks assuming there is still plenty of surface agitation?


The turnover rate has nothing to do with the way oxygen gets into the water. You can have a tank with a 2,000gph filter and a submerged filter outlet that doesn't ripple the surface, and the oxygen content in water will be very low. If you put a 20gph filter on the same tank with a spray bar that is mounted above the water surface raining water down into the tank, the oxygen content might be at saturation levels.



Ensorcelled said:


> Secondly, more of a chain question from the above regarding surface agitation. I noticed that you mentioned and use the eheim diffusor (thanks for the great video too!). Within your video I notice that you don't seem to have much surface agitation, yet you do have the Eheim 2260 standalone running only the diffusor. What I am curious about is if your oxygen saturation would be the same or less if you ran the 2260 with a spraybar (no diffusor) for surface agitation and theoretically additional equipment for surface or non-surface agitation (i.e. powerhead pointing up towards the surface or down towards an intake for floating debris)?


Oxygen will dissolve in water wherever air and water meet. That is obviously the case at the tank surface, and you can increase this surface a little if you ripple it. That is the reason rippling can increase the oxygen content in water. However, air and water also meet at the surface that surrounds every single air bubble that is in the water. If you have a few big bubbles from a airline without a airstone, the combined surface of all the bubbles is probably smaller than the rippled tank surface. That's why the bubbles play only a minor role. But a lot of tiny bubbles have a much larger combined surface than a few big bubbles. This can be shown by maths if you calculate the surface area of the bubbles, but I hope you are going to take my word for it! An airstone produces smaller bubbles, so it will increase the combined bubble surface, but a diffusor creates gazillions of very tiny bubbles, meaning the combined bubble surface will be huge. Knowing that this surface is so huge makes me confident to claim that with a diffusor oxygen is always at saturation levels. Despite oxygen being consumed in the tank, there is so much surface in which air and water meet that it can be immediately replenished from the air.



Ensorcelled said:


> I have read your article on your website about 2-3 times over to try to really grasp what you are presenting here. I don't want my questions to seem "challenging" as I am really just trying to get a full understanding on this.


No problem. I hope I have been able to clear things up a little.


----------



## BillD (May 17, 2005)

fmueller said:


> [
> 
> The
> 
> ...





> The outcry wouldn't come from me! However, I don't know anybody who uses UGFs and cleans them as often as once every 6 months. Keep in mind that a UGF will not be clean after a gravel vacuuming. To get an UGF as clean as a canister, you need to completely dismantle the tank, remove the substrate, and get under the plates. Most people do this never while the tank is in operation.
> 
> Another big difference is that oxygenated water circulates through an entire canister filter. Certainly in my canister filters there are no dead spots and there is no anaerobic decomposition going on in there. If it was, I could certainly smell it upon opening the filter. If you have ever broken down a tank that had an UGF installed, you will certainly remember the smell of rotten eggs indicating H2S, the product of anaerobic decomposition.


The last tank I had with UGF was set up over 12 years. When I broke it down, there was no anaerobic smell. i also discovered by observing from below, that a siphon hose inserted down the uplift tube to the plate removed the debris beneath the plate.


> When I open my canister filters, they contain no plant parts or anything that could be broken down further. The nitrifying bacteria have long ago broken down anything they could digest, and the resulting nitrate has been removed via water changes. If that wasn't so, I could not have nitrate at undetectable levels with tanks that have the filters cleaned only once every 6 months. The debris left in the filter is inert material which does no harm, and I am happy for the filter to store it until I get around to removing it.


We need to differentiate between the work done by nitrifying bacteria which break down ammonia products (metabolic waste), and heterotrophoic bacteria which break down solids (digestive waste) and create ammonia. Both are aerobic bacteria and compete for any available oxygen in a filter. The debris in the filter is not inert, if it is fecal matter.


----------



## BillD (May 17, 2005)

I'm not trying to discredit what fmueller has stated, because clearly his method works. It is interesting to see what is actually happening here, and discussions of this type, are the forte of forums. I think we tend to underestimate the biological filtration capability of the hard surfaces in the tank, which are covered with biofilm. This of course will vary from one tank setup to another, but is probably more significant than is generally considered.


----------



## Ensorcelled (Mar 1, 2011)

Fmueller- Thanks so much for your informative reply to my questions!

I would like to however ask another question regarding that video you posted on your 125G setup. Like I pointed out, you have the diffusor going with your Eheim and the outlet is pointed downards not towards the surface. I could be wrong here but from what I saw, I am taking a guess that you don't have much surface "ripplage" going on? So does this mean that the gazillion microbubbles produced by the diffusor keeps the tank at very high oxygen saturation levels despite the lack of ripples on the surface?


----------



## fmueller (Jan 11, 2004)

BillD said:


> We need to differentiate between the work done by nitrifying bacteria which break down ammonia products (metabolic waste), and heterotrophoic bacteria which break down solids (digestive waste) and create ammonia. Both are aerobic bacteria and compete for any available oxygen in a filter. The debris in the filter is not inert, if it is fecal matter.


I feel the only thing we disagree on is the time frame in which these things happen. In my opinion both the breaking down of poop (I am using a technical term here  ) into ammonia and the conversion of ammonia to nitrate happen fast, as long as enough oxygen is present. I am guessing hours. In the case of plant parts or other larger particles we might be talking days. After that process is completed, the material is inert. It's not like the material sits around for months and keeps on decomposing. If that is true, you would need to clean your filter daily to catch the waste before it is broken down to ammonia. I am not prepared to do that, and I don't think it's necessary. Whether I clean my filter every 4 weeks or every six months in this scenario does not matter, as long as there is enough space in the filter for both types of bacteria to do their job, as well as for storage of the inert material. I wish I had the scientific data to back this up as a fact, but I don't. But I reckon it's a reasonable assumption, because it's based on observations made during a number of years of fish keeping by somebody with a bit of a science background 



BillD said:


> I'm not trying to discredit what fmueller has stated, because clearly his method works. It is interesting to see what is actually happening here, and discussions of this type, are the forte of forums. I think we tend to underestimate the biological filtration capability of the hard surfaces in the tank, which are covered with biofilm. This of course will vary from one tank setup to another, but is probably more significant than is generally considered.


No harm done. I too enjoy the discussion.



Ensorcelled said:


> Fmueller- Thanks so much for your informative reply to my questions! I would like to however ask another question regarding that video you posted on your 125G setup. Like I pointed out, you have the diffusor going with your Eheim and the outlet is pointed downards not towards the surface. I could be wrong here but from what I saw, I am taking a guess that you don't have much surface "ripplage" going on? So does this mean that the gazillion microbubbles produced by the diffusor keeps the tank at very high oxygen saturation levels despite the lack of ripples on the surface?


My pleasure, and you summarized my point exactly. As you have seen in the video, there is virtually no rippling in my 125G. There is absolutely no rippling in my 240G, where the water surface in the tank is perfectly still. The return from the sump happens via an UGJ system. The oxygenation happens in the Durso standpipes where the water exits at the bottom as a foam akin to what you see at the bottom of the Niagara Falls - well not quite, but two 1800gph pumps at full flow pushing water through two 2" Durso standpipes are a beautiful sight to any fish keeper 

For oxygenation any surface where air and water meet matters. It doesn't have to be the surface at the top of the tank.


----------



## countryboy814 (Feb 19, 2012)

BillD said:


> There have been some interesting opinions as well as facts presented in this thread.
> 
> 
> fmueller said:
> ...


Although Dr. Tim is a cutesy little monacher, is there a last name? The second sentence, above, sounds pretty familiar...maybe from his store site?


----------



## GTZ (Apr 21, 2010)

Dr. Tim Hovanec Ph.D. The sentence you're referring to is somewhat similar to something Dr. Tim posted in the original thread before it was split.


----------



## vann59 (Jun 20, 2011)

I know that marineland makes a bio wheel that accompanies canister use, but it does hang on the back of the tank. I occurs to me now that it would be a good idea to have a bio wheel kit to use in a canopy that can be fed water with either a hose using a splitter line, or a very small pump that would send water over the wheel. This could all be done inside the canopy in a hidden manner, at least in my theory. Maybe a DIY model could be made with some large diameter pvc pipe as the bio wheel housing.


----------



## 13razorbackfan (Sep 28, 2011)

vann59 said:


> I know that marineland makes a bio wheel that accompanies canister use, but it does hang on the back of the tank. I occurs to me now that it would be a good idea to have a bio wheel kit to use in a canopy that can be fed water with either a hose using a splitter line, or a very small pump that would send water over the wheel. This could all be done inside the canopy in a hidden manner, at least in my theory. Maybe a DIY model could be made with some large diameter pvc pipe as the bio wheel housing.


OR...make a very long set of bio wheels with some sort of rigid support...maybe 20" long. Instead of using a spray bar you could use two of those and spread the water evenly although you would have to have a pretty good flow but in my tank that is no problem.

It would probably be pretty easy to build if I had all the supplies needed. Just make a tray for the return from the canister to pour into and make your own bio wheel. The design of the bio wheel is pretty simplistic. Although over a span that long I imagine the material used in the bio wheels currently would sag quite a bit. That would be a really fun project though.


----------



## fmueller (Jan 11, 2004)

countryboy814 said:


> he second sentence, above, sounds pretty familiar...maybe from his store site?


I assume you are referring to my sentence:



fmueller said:


> His observations were made under controlled conditions in a laboratory environment and the results of his work were published in peer reviewed scientific journals.


I did not copy it from anywhere, but just wrote it. I admit that terms like 'controlled conditions in a laboratory environment' and 'peer reviewed scientific journals' might look odd in a fish forum at first glance, but they are common in academic circles. They are not meaningless phrases, but they describe the way in which knowledge is acquired in modern society. You need to work in this way if you want to do research at a university or another reputable institute. In the US, major funding organizations like the National Science Foundation (NSF) and the National Institute of Health (NIH), will also pay attention to researchers adhering to these standards when they apply for money, which they need to do their research. In a nutshell, working in this way means that you don't believe stuff because others told you it's so, or simply because you want to believe it, but you rely on the scientific method, and present results that are reproducible and as objective as possible; that is you are not a religious zealot or snake oil salesman


----------



## Fishy_Cichlid (Aug 4, 2011)

This is a very informative post. I had posted some information on oxygenation in the forum some time back, so this post goes to reinforce those views -

1. Oxygenation takes place just not on the water surface but also within the water body through diffusion created by air bubbles from an aerator.
2. Finer air bubbles create more surface area for oxygen diffusion than bigger bubbles. In this context, I would also like to say that its not just the surface area but also the compression/pressure it creates in finer bubbles (which is more in-elastic, in a scientific way of meaning) than a bigger bubble. Air/Oxygen enters the inter-molecular space between the H2O molecules, and hence for Oxygenation, breaking the surface tension of the H2O molecules is important.

The fact that Dr. Tim mentions that the Bio-film that the bacteria creates is quite robust in an established tank is very informative. I would however appreciate if Dr. Tim could answer a question on the Nitrification issue.

Say, it take T1 time for a single bacteria to convert 1 unit of Ammonia. So, if the tank is producing Q units of Ammonia daily, the "optimum" numbers of bacteria should be around Q numbers to convert all the Q units of Ammonia into Nitrites in T1 time. So each of the bacteria is getting its daily quota of food. But what prevents the bacteria to multiply into say x2 times the numbers even after daily availability of food ? Does it mean, that the bacterias are able to understand the Ammonia load from the Ammonia concentration in water and will only then multiply ?

I think, no matter how low the Ammonia load might be, the total conversion time remains the same upto the optimum Ammonia load for a predefined available bacterial surface area. I say this because 2 bacteria cannot process a single unit of Ammonia in half the time. So, upto the optimum Ammonia load, the Total Ammonia conversion time remains constant. However, if the Ammonia load increases beyond the optimum load, then - either the bacteria has to multiply or the conversion time increases. In case of the former, there has to be again sufficient area for the Bacteria to reside. Otherwise, the Ammonia conversion time just increases.


----------



## countryboy814 (Feb 19, 2012)

fmueller said:


> countryboy814 said:
> 
> 
> > he second sentence, above, sounds pretty familiar...maybe from his store site?
> ...


I have never believed stuff because someone told me it was so. Well....maybe Santa. If I did I would have 4 canisters, 2 heaters, three ac 110s on my 55 gal.


13razorbackfan said:


> vann59 said:
> 
> 
> > I know that marineland makes a bio wheel that accompanies canister use, but it does hang on the back of the tank. I occurs to me now that it would be a good idea to have a bio wheel kit to use in a canopy that can be fed water with either a hose using a splitter line, or a very small pump that would send water over the wheel. This could all be done inside the canopy in a hidden manner, at least in my theory. Maybe a DIY model could be made with some large diameter pvc pipe as the bio wheel housing.
> ...


I prefer to get things off the backs my tanks not add to them. That was the idea behind my canisters and inline heaters.


----------



## countryboy814 (Feb 19, 2012)

Fishy_Cichlid said:


> This is a very informative post. I had posted some information on oxygenation in the forum some time back, so this post goes to reinforce those views -
> 
> 1. Oxygenation takes place just not on the water surface but also within the water body through diffusion created by air bubbles from an aerator.
> 2. Finer air bubbles create more surface area for oxygen diffusion than bigger bubbles. In this context, I would also like to say that its not just the surface area but also the compression/pressure it creates in finer bubbles (which is more in-elastic, in a scientific way of meaning) than a bigger bubble. Air/Oxygen enters the inter-molecular space between the H2O molecules, and hence for Oxygenation, breaking the surface tension of the H2O molecules is important.


Why do ppl work so hard to get rid of microbubbles?


----------



## fmueller (Jan 11, 2004)

countryboy814 said:


> Why do ppl work so hard to get rid of microbubbles?


When you find out, please make sure to let me know as well 

Kidding aside, from what I have heard, the idea is that microbubbles, when sucked into an impeller pump, could eventually fill the impeller chamber with air and stop the pump. I have never known anybody who actually encountered that problem, but it's frequently discussed online. My theory is that this assumption that microbubbles could be bad for fish tank pumps lead to the statement that microbubbles are bad for fish tanks, which developed into the urban myth that microbubbles are bad for fish.

As far as fish go, the more oxygen in the water, the better they are off. This is especially true for fish whose natural habitat is highly oxygenated water, such as the surge areas of the Rift Lakes (eg Tropheus), and fish that live in rapids of major rivers (many plecos). Granted, there are some fish that live in bodies of water that experience severe drought conditions, and have adapted to be able to tolerate very low oxygen levels - bettas and killies would be good examples. Yet while those fish can tolerate lower oxygen content, it stands to reason that even they will do better in well oxygenated water.

I just tried to come up with some underwater footage of Tropheus in Lake Tanganyika, and found the video below. Sorry, the narrative is in German, but you can clearly see that Tropheus live in rocky areas in water depth of less than 3'. Even in the mild weather conditions under which the video was shot, you can see some bubbles entering the water due to waves (eg around 6:07min). Imagine what that water will look like on a windy day or during a storm! If those fish could not cope with bubbles, they would have died out with the dinosaurs!


----------



## Fishy_Cichlid (Aug 4, 2011)

The fear of air-bubbles entering the pump in an aquarium is ill-founded. The effect is known as PRIMING. Priming of a pump (effect of air bubbles entering the pump) can be a issue only if the water/liquid that is being pumped is below the pump level. Impellers are unable to compress the air out, thereby creating suction for the water/liquid to be sucked into the pump casing. However, in case of an aquarium, the pumps used are usually the immersible type, be it inside the aquarium or inside the sump. In such a case, the effect of micro-bubbles is almost negligible. Air is lighter than water and will always tend to rise to the surface. Even if the pump isnt a "self-priming" pump (most aquarium pumps are not self priming), the fear of a few bubbles entering the pump is not founded.

http://www.gongol.net/knowledgebase/selfpriming/

Self-priming pumps have a chamber built in the suction side that store water even when the pump is not running. Thus its able to start up even if the inlet line has air inside by mixing with this stored water and starting the suction process.


----------



## Ensorcelled (Mar 1, 2011)

Fmueller - Thanks again for all the fantastic information you have presented along with everyone else within this thread. I love it when this kind of discussion can take place and everyone can learn a thing or two! 

So from the information regarding microbubbles inside canisters from the intakes sucking them in to where it stops them from operating correctly over time is mainly just a "thing"? I too, have personally never encountered or heard of anyone else encounter this problem. Which leads me to question a concept that the well known FX5 employs by stopping the filter and purging excess air every 24hrs. I wonder if this was their way of combating microbubbles being sucked up over time or just an overall marketing gimmick? Either way, I don't think I would personally trust the whole shutting down every 24hrs for fail reasons but I'll save that debate for when a thread discussing that issue arises.


----------



## vann59 (Jun 20, 2011)

Air purge appears to be the reason for the daily stop, but on the FX5 the pump is on the bottom, so it wouldn't likely lose prime anyway.


----------



## DrTim's (Jun 8, 2010)

fishy-cichlid - you wrote/asked



> Say, it take T1 time for a single bacteria to convert 1 unit of Ammonia. So, if the tank is producing Q units of Ammonia daily, the "optimum" numbers of bacteria should be around Q numbers to convert all the Q units of Ammonia into Nitrites in T1 time. So each of the bacteria is getting its daily quota of food. But what prevents the bacteria to multiply into say x2 times the numbers even after daily availability of food ? Does it mean, that the bacterias are able to understand the Ammonia load from the Ammonia concentration in water and will only then multiply ?


It is not that simple. The conversion of ammonia to nitrite and nitrite to nitrate are what is called "first order reactions". This means the rate of the conversion of the ammonia/nitrite depends on the concentration of the ammonia/nitrite. The more ammonia/nitrite the faster the rate. So if you have two bacteria and one was in a liquid with 1 mg/L NH3-N and the other in a liquid with 2 mg/L NH3-N, the bacterium in the 2 mg/L NH3-N solution would be converting the ammonia faster than the bacterium in the 1 mg/L NH3-N solution. Yes rate calculations can be made but they are not simple arithmetic.



> I think, no matter how low the Ammonia load might be, the total conversion time remains the same upto the optimum Ammonia load for a predefined available bacterial surface area. I say this because 2 bacteria cannot process a single unit of Ammonia in half the time. So, upto the optimum Ammonia load, the Total Ammonia conversion time remains constant. However, if the Ammonia load increases beyond the optimum load, then - either the bacteria has to multiply or the conversion time increases. In case of the former, there has to be again sufficient area for the Bacteria to reside. Otherwise, the Ammonia conversion time just increases.


Again not as simple as you write but I understand your thinking. But cells and cellular processes are more complex plus there are feedbacks, both negative and positive, that effect the rate. For instance, pH. The ammonia bacteria use ammonia (NH3) not ammonium (NH4+). But as the pH of the water drops more and more of the total ammonia goes into the NH4+ form that the bacteria cannot use. Also as the bacteria convert NH3 to NO2- they produce hydrogen ions (H+) which causes the pH of the water to drop thus slowing the conversion because more of the total ammonia is going into the NH4+ form.

A practical problem that arises from this is when you are doing a fishless cycle using ammonia. The more ammonia you add the more of the hydrogen by-product produced and so the pH drops and the conversion of ammonia slows or stops (at low pH values). The tendency is for the hobbyist to add too much ammonia without buffering the water to keep the pH up (at least above 7 by near 8 is even better) so the conversion of ammonia stops.


----------



## 13razorbackfan (Sep 28, 2011)

DrTim's said:


> *
> A practical problem that arises from this is when you are doing a fishless cycle using ammonia. The more ammonia you add the more of the hydrogen by-product produced and so the pH drops and the conversion of ammonia slows or stops (at low pH values). The tendency is for the hobbyist to add too much ammonia without buffering the water to keep the pH up (at least above 7 by near 8 is even better) so the conversion of ammonia stops*.


That is a great point...


----------



## Fishy_Cichlid (Aug 4, 2011)

Thanks so much Dr. Tim for taking the time to explain. I do get your point. Its very logical & scientific and I really liked the way you made it so simple for me. Perhaps the decay in the rate is logarithmic and maybe after all the studies you have done on the above subject, you do have a equation of rate vs PH and any other factor which might be affecting the rate.

Sorry for continuing to ask you question but really, I would like to know more. As you mentioned -
1. As PH drops, more is being converted into NH4, so we have less NH3 concentration. Implying the rate slows down since you said higher concentration leads to a faster rate of Nitrification.
2. As NH3 is being converted into NO2, more H+ ions are released making the water more acidic ... lowering the PH. So again, the rate drops.

Now, instead of adding less Ammonia during a fishless-cycle, where a majority might be converted into NH4 form, thus lowering the nitrification rate, couldn't we add more Ammonia (so that concentration is high - so a faster rate) and at the same time adding enough Buffers to get hold of the H+ ions so that PH and thus the Nitrification rate too isn't lowered ??

Another question after reading all your replies here in this post : Do you mean to say that there are several species of Ammonia converting & Nitrite converting bacteria forming normally (without addition of any bottled bacteria) during the cycling process ? If so, then some of them maybe more efficient. What are those bacterias and how can one increase the proportion of such efficient bacteria in a tank ?

Are there any specific types of bacteria (bottled) which can lower Nitrates in a tank by converting it into N2 ? I am not speaking of any process like De-Nitrifying process some people achieve by installing a De-Nitrifier which IMO can be quite a hassle and not so effective. And is De-Nitrifying process always Anaerobic ? Any chemical which can bind to the Nitrate without affecting the Physiology of the fishes in the tank ?

Sorry for asking too many questions, my apologies please.


----------



## Fishy_Cichlid (Aug 4, 2011)

Dr Tim, I did try to find out research articles on this very subject a few months back and had even posted it here in CF. Some of the references, I did find, matches exactly what you had posted here in this post. However, many of the articles were to be purchased if someone needed to view the full paper. Again, some of them did not go into a detailed explanation and in a form which was easier for us to understand. But, in short, the articles did say exactly what you told us in this post. Here are the links of some of them which I had saved in my PC -

http://www.wastewaterhandbook.com/docum ... netics.pdf
http://www.springerlink.com/content/u63 ... 64/?MUD=MP
http://www.sciencedirect.com/science/ar ... 2408002009

Would be nice if you could explain a little more in details.
Regards Jay


----------



## Dawg2012 (May 10, 2012)

Wow... Lots of knowledge gained on this lunch hour and a half!


----------



## DrTim's (Jun 8, 2010)

> Thanks so much Dr. Tim for taking the time to explain. I do get your point. Its very logical & scientific and I really liked the way you made it so simple for me. Perhaps the decay in the rate is logarithmic and maybe after all the studies you have done on the above subject, you do have a equation of rate vs PH and any other factor which might be affecting the rate.


I think it is more calculus than logarithmic! I will try to find you an equation but it is not 'clear'. Much depends on temperature, salinity and other environment factors - this is biology (i.e., messy) not chemistry!



> Sorry for continuing to ask you question but really, I would like to know more. As you mentioned -
> 1. As PH drops, more is being converted into NH4, so we have less NH3 concentration. Implying the rate slows down since you said higher concentration leads to a faster rate of Nitrification.
> 2. As NH3 is being converted into NO2, more H+ ions are released making the water more acidic ... lowering the PH. So again, the rate drops.
> 
> Now, instead of adding less Ammonia during a fishless-cycle, where a majority might be converted into NH4 form, thus lowering the nitrification rate, couldn't we add more Ammonia (so that concentration is high - so a faster rate) and at the same time adding enough Buffers to get hold of the H+ ions so that PH and thus the Nitrification rate too isn't lowered ??


Yes, exactly which is why one of first questions to people who say their cycle is stuck is "what is your pH". When we culture this bacteria we have to continuously add buffer as we add ammonia to counteract the production of the hydrogen ions.



> Another question after reading all your replies here in this post : Do you mean to say that there are several species of Ammonia converting & Nitrite converting bacteria forming normally (without addition of any bottled bacteria) during the cycling process ? If so, then some of them maybe more efficient. What are those bacterias and how can one increase the proportion of such efficient bacteria in a tank ?


The short answer is yes and no. There may be several species of AOB and NOB but the ones you want are the ones that grow under the best aquarium conditions not necessarily the ones you could grow fastest. I do into great detail about this with a study we published. You can download a pdf of the paper here

http://www.drtimsaquatics.com/resources/library-presentations/scientific-papers it is the second paper down published in 2001. it talks about different AOB.



> Are there any specific types of bacteria (bottled) which can lower Nitrates in a tank by converting it into N2 ? I am not speaking of any process like De-Nitrifying process some people achieve by installing a De-Nitrifier which IMO can be quite a hassle and not so effective. And is De-Nitrifying process always Anaerobic ? Any chemical which can bind to the Nitrate without affecting the Physiology of the fishes in the tank ?


by definition denitrification is the conversion of nitrate to di-nitrogen (N2) so the answer is no there are no bacteria in a bottle that convert nitrate to N2 without denitrifying (again by definition).

Now there are bacteria that can assimilate nitrate into cells growth and lower nitrate but they do not produce N2 (my waste-away bacteria do this)



> Sorry for asking too many questions, my apologies please.


No worries, just be patient with me as I cannot always answer immediately


----------



## Fishy_Cichlid (Aug 4, 2011)

> No worries, just be patient with me as I cannot always answer immediately


Thanks so much Dr. Tim. It will also take me some considerable time to go through your research articles and assimilate it :lol: :lol:

However, I feel one question that I had put up didnt get answered completely. 


> Now, instead of adding less Ammonia during a fishless-cycle, where a majority might be converted into NH4 form, thus lowering the nitrification rate, couldn't we add more Ammonia (so that concentration is high - so a faster rate) and at the same time adding enough Buffers to get hold of the H+ ions so that PH and thus the Nitrification rate too isn't lowered ??


*If, I buffer the tank water regularly during the cycle, testing PH very often and not let it fall (say, below 7.8 or 8.0), can I add Ammonia more than 5ppm, so that the cycle is completed faster. I say this, because you had mentioned that keeping the Ammonia concentration higher increases the conversion rate for the Nitrification bacteria.*

Thanks again.


----------



## DrTim's (Jun 8, 2010)

Hello



> However, I feel one question that I had put up didnt get answered completely.
> 
> Now, instead of adding less Ammonia during a fishless-cycle, where a majority might be converted into NH4 form, thus lowering the nitrification rate, couldn't we add more Ammonia (so that concentration is high - so a faster rate) and at the same time adding enough Buffers to get hold of the H+ ions so that PH and thus the Nitrification rate too isn't lowered ??
> 
> If, I buffer the tank water regularly during the cycle, testing PH very often and not let it fall (say, below 7.8 or 8.0), can I add Ammonia more than 5ppm, so that the cycle is completed faster. I say this, because you had mentioned that keeping the Ammonia concentration higher increases the conversion rate for the Nitrification bacteria.


The answer is no and the reasons, in great detail, are in the paper I sent you to. If you add too much ammonia you end up growing the wrong ammonia-oxidizing bacteria (AOB). Ones that grow in high ammonia environments but not in low ammonia environments. Ok, so what's 'high' and what's 'low'. Again that question is answered in detail in the paper and the answer is that around 5 mg/L ammonia-nitrogen you get a shift from one group of AOB to another.

This was part of key to my developing BioSpira and being awarded 13 patents. In the past some company's sold nitrifiers and they did not work. These mixes included _Nitrosomonas europaea_ which is found in sewage treatment plants (very high ammonia environment) so why didn't they work? What I was able to show is that this AOB (_N. europaea_) does not grow in aquaria - there were new AOBs and these new ones only grow in low ammonia environments while _N. europaea_ will only grow in high ammonia environments.

So the ammonia concentration matters.


----------



## Fishy_Cichlid (Aug 4, 2011)

Thanks Dr.Tim, so much for your patience & your time in answering my questions. I went through your papers, infact, all of them and at length several times. It was difficult at times to understand buy yes, I did get the synopsis and also the answers to my questions there itself. Its amazing, since I just knew (as of today) that it was just a Nitrosomonas bacteria that was responsibe for the Ammonia Nitrification. And I also understand why the N2 cycle period varies in length for different people cycling their tanks.

Thanks again, so much.
Regards - Jay


----------



## B.Roberson (Nov 6, 2011)

So 13 razorback I have a question, and I'm no expert, so what we've read and heard from Dr Tim he doesn't like the Bio in a watertight container?? I don't mean to take anyone off the track they were going but what I heard was he didn't like that. So do you, or anyone keep the Bio eg: ceramic, stars, etc out of their canisters? 
I have a 75 gal wth a canister and a hob, ac110. Would anyone want to put most Bio in the hob so the FILM doesn't build up too thick, as you can rinse it more readily, and keep more mechanical in the canisters??. This has probably been answered but thanks anyway..


----------



## 13razorbackfan (Sep 28, 2011)

B.Roberson said:


> So 13 razorback I have a question, and I'm no expert, so what we've read and heard from Dr Tim he doesn't like the Bio in a watertight container?? I don't mean to take anyone off the track they were going but what I heard was he didn't like that. So do you, or anyone keep the Bio eg: ceramic, stars, etc out of their canisters?
> I have a 75 gal wth a canister and a hob, ac110. Would anyone want to put most Bio in the hob so the FILM doesn't build up too thick, as you can rinse it more readily, and keep more mechanical in the canisters??. This has probably been answered but thanks anyway..


Yes....and one of the main reasons is what you mentioned in regards to the biofilm being smothered by gunk and other types of bacteria that we don't really want. So I posed the question would it be better to rinse the biomedia during filter cleanings making sure not to scrub but to gently dip in old or dechlorinated tank water. His answer was yes. So when I clean my filters, I clean one filter at the first of each month and the other filter the first of the next month and so on, I make sure to dip my ceramic rings gently(maybe gently is the word because I used some force and quickness in dipping them just making sure I don't scrub it off as this knocks off most of the buildup) when I clean the filter.

I think as far as placement I have always preferred to keep my filters loaded with both bio and mechanical as to limit mini cycles or if one fails. I have not had any issues. I have so much bio media split between both my filters that I don't think it is necessary to clean more than once every two months. Then again I have two giant filters on my 75g. Together they probably hold about 8 gallons of water.


----------



## B.Roberson (Nov 6, 2011)

And that's what I was gathering also, thanks for the assurance. I've been kinda doing that anyway as far as rinsing the ceramic rings, both my filters have some. My canister also has some (stars) Rena xp3.
But I only clean the canister every other month. The AC 110 I rinse the media weekly with WC, and lightly rinse the Bio...
Sound right??


----------



## 13razorbackfan (Sep 28, 2011)

B.Roberson said:


> And that's what I was gathering also, thanks for the assurance. I've been kinda doing that anyway as far as rinsing the ceramic rings, both my filters have some. My canister also has some (stars) Rena xp3.
> But I only clean the canister every other month. The AC 110 I rinse the media weekly with WC, and lightly rinse the Bio...
> Sound right??


Sounds fine to me. If your parameters are staying within reason then I would say you are fine. I have always stuck with a routine. Whatever you decide to do just stick with it if it is working for you.


----------



## Tex Chappy (Dec 25, 2013)

Resurrect time 

I have a couple of questions about what I've read in this thread:

1. Have Dr. Tim's views stood the test of tim in the last couple of years?

2. If Dr. Tim doesn't like canister filters for Bio - what is the preferred setup for Bio and Mechanical filtration?

3. What about the rest of Dr. Tim's 'maintenance' bacteria products?


----------

