# OF HYDRA 30



## johnchor

has anybody uses this filter before?

it claims to convert amonia to nitrogen in 1 cycle. 

http://www.arofanatics.com/forums/showt ... p?t=473667


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## fmueller

I haven't used it, but I have just watched the associated YouTube video by the manufacturer. The claim is that the filter uses a catalyst, which coverts all harmful nitrogen compounds (ammonia, nitrite, and nitrate) into gaseous nitrogen (N2). If true, N2 would leave the tank as gas, and enter the air. N2 makes up 80% of the air anyhow, which means it is a completely harmless and odorless gas. An ideal solution!

The sensation in this is that you get rid of nitrate, which is the end product of the nitrogen cycle, and usually accumulates in our tanks until we perform a water change. If you wanted to show that the new catalytic filter works, you would show a curve that displays the concentration of nitrate over time. In a tank not using the new catalyst material, the nitrate concentration should continue to increase. In a tank using the new catalyst material, the nitrate concentration should go to zero or a very low level, and remain there for a very long time, that is until the catalyst material is exhausted.

The makers of this new filter actually show a nitrogen concentration curve in this YouTube video and also here. I have embedded the diagram below this paragraph for your convenience. Unfortunately the curve for the tank using the catalyst (blue curve) does not show a decreasing and then stabilizing nitrate concentration. Instead, the nitrate concentration bounces around quite a bit. At the end, which is the most critical period, it is actually going up, which contradicts the claim that nitrate is removed via conversion to N2.










What also strikes me is that in the comparison tank not using the catalyst, neither the ammonia concentration nor the nitrite concentration are zero (red curve), as they should be in any cycled tank (see diagrams below). This proves that the comparison tank was not cycled, and suggests that a newly set up tank was used. With the measurement being conducted for 21 days only, beneficial bacteria never had a chance to become established. What happens in a tank during the cycling period depends on so many variables that using it as comparison makes the study entirely meaningless. Since the main advantage of the catalyst lies in the long term nitrate removal, it should be compared to a stable tank with fully cycled biological filter!










Looking at all the curves the makers of this new filter present, I can not help but notice that they agree perfectly with a situation in which ammonia, nitrite, and nitrate are temporarily bound by a material like Zeolite. One would expect the nitrate to be bound the least well, and you can actually see the nitrate concentration go up towards the end of the test - at which time the test was conveniently terminated! To give this new product any credibility, one would need to see how all of these curves progress for another month or two. If the results had been in the manufacturer's favor, I am sure they would have been shown :wink:


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## notQH

http://www.arofanatics.com/forums/showt ... ht=hydra30

http://www.arofanatics.com/forums/showt ... ht=hydra30

the curves are only very small part of the entire research. If you want to know more about the topic, you can pm me or I post it here.


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## fmueller

notQH said:


> the curves are only very small part of the entire research. If you want to know more about the topic, you can pm me or I post it here.


Welcome to CF!

Have you compared your catalyst filter to a fully cycled biological filter, and can you show that your filter reduces the nitrate concentration in tank water?


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## notQH

this was taken during the testing. one control tank, one reactor tank. same size, same type of fish. same numbers of fish, take sample to compare daily.

by the way, the orgional reactor is not for fish, it is the industrial unit that has been use for many years. but much bigger size, up to 10 M3 ...


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## notQH

we kill many fish/fishes during the exercises. 90% of our time, we try to find a way to remove ammonia and at the same time would not harm the fish, different type of fish as well, and plants, turles etc. After few years and hundred of thousands of units being sold worldwide in both fresh water and sea water, we are glard to know that no report saying that the fish were kill. What we are doing is the second strongest oxidant in nature.


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## fmueller

I take that as a no on both of my questions.


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## notQH

ok, the answer is:

1. each testing withh have catalyst filter and a fully cycled biological filter to compare the result

2. nitrate concentration will monitor daily for many months for both sea and fresh water tank.


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## fmueller

If you collect data for a comparison with a fully cycled biological filter (which would be relevant), why does your web site show data of a comparison with an uncycled biological filter (which are irrelevant)?

Also, if you monitor nitrate concentrations daily for many months, why does your web site show data for the first 21 days only? And why does the nitrate concentration increase at the end of the period, which contradicts the claim that nitrate is removed via conversion to N2?

Can you show relevant data? This is a site concerned with freshwater fish keeping only. Freshwater data will be fully sufficient, no saltwater data are required :thumb:


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## notQH

the reaction is to remove Ammonia from water. Once Ammonia can remove, nitrite nitrate will not build up.


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## notQH

when we use two different tanks, we need to make sure the "control tank" fish numbers will be the same as the one with reactor. And the feed will be the same. For instance, we will put 200 gold fish in both tanks. However, the "control tank" fish number will decline after a period of time if we do not change water at all. Of course, we can ADD fish but it will make the entire testing meaningless since the "feed" has been changed. To deal with living things is not easy, so the testing will not be able to last too many months. Of course, we can just use 2-3 fish for the testing but it will not generate significant result.


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## fmueller

OK, you claim you have difficulties obtaining data for the control tank. Let's assume that's true, but that's not what I asked about. I asked about the nitrate concentration in the test tank (the one with your catalyst filter). You should be able to show data for that tank. And you should be able to explain why the nitrate concentration increased in that tank towards the end of your test period. That's exactly what one would expect to see in a tank without your filter - or if your filter didn't work! I am talking about the diagram below.  See how the blue curve goes up at the end? It shouldn't do that if your filter was working!










I am also still wondering why you used an uncycled control tank to collect all the data I have ever seen from you.


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## notQH

fmueller said:


> OK, you claim you have difficulties obtaining data for the control tank. Let's assume that's true, but that's not what I asked about. I asked about the nitrate concentration in the test tank (the one with your catalyst filter). You should be able to show data for that tank. And you should be able to explain why the nitrate concentration increased in that tank towards the end of your test period. That's exactly what one would expect to see in a tank without your filter - or if your filter didn't work! I am talking about the diagram below. See how the blue curve goes up at the end? It shouldn't do that if your filter was working!
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> I am also still wondering why you used an uncycled control tank to collect all the data I have ever seen from you.


 thanks for you advice. I will forward your question to the manufacturer - QH. in fact, i believe all the data should be avaliable to the end uers. by the way, the document may came from the patent agent or patent lawyer ...


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## fmueller

notQH said:


> I will forward your question to the manufacturer - QH. in fact, i believe all the data should be avaliable to the end uers.


Many thanks. I appreciate that. Please do let us know if you here anything back that seems relevant to our discussion.

*To summarize this thread for anybody not willing to read the entire exchange in detail, all data so far published by the manufacturer of this line of filters suggest that the filter is not working as advertized.*


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## notQH

the new algae remove unit is better to understand since the algae in the tank will physical disappear. this is to replace UV that can not do the job. So far, no advertisment out yet.


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## newforestrob

you say 90% of the time you are trying to remove ammonia,and many fish are killed,in a properly cycled tank,ammonia is converted,basic nitrogen cycle,I must be missing something here :-? 
thanks frank for asking the right questions,the answers on the other hand :zz:


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## notQH

newforestrob said:


> you say 90% of the time you are trying to remove ammonia,and many fish are killed,in a properly cycled tank,ammonia is converted,basic nitrogen cycle,I must be missing something here :-?
> thanks frank for asking the right questions,the answers on the other hand :zz:


basically, if Ammonia being remove, there will be no NO2 and NO3...NH4-N to N2, not the traditional nitrogen cycle.


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## notQH

Marine Tank Hydra 30 Internal Filter QH Shop for Over 6 Months, water top up only, no sponge 2012-07-19-0685


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