# Cyanobacteria again



## JimA (Nov 7, 2009)

I had it in the tank about 6 plus months ago and treated with erythromycin and it went away instantly. I read up on the causes and have been diligent about water changes and substrate cleaning, which I thought I was doing pretty good already. I also upped the circulation in the tank and lowered the water level a bit so the filter returns were creating good surface agitation. But now it has started to show up again. I have heard using the antibiotics may quit working at some point, but at 6 moth plus intervals would have that problem? Just not sure why I am getting it? Phosphates from the well, too much light maybe. Kinda stumped at this point. 

I have read enough to make me blind on the internet about it, so just looking for some other thoughts/info would be great!

Jim


----------



## DJRansome (Oct 29, 2005)

What kind of lighting do you have? I have tanks with LED lights (no algae) and one with fluorescents and OLD bulbs...algae.

Do you have any plants in the tank?


----------



## JimA (Nov 7, 2009)

DJRansome said:


> What kind of lighting do you have? I have tanks with LED lights (no algae) and one with fluorescents and OLD bulbs...algae.
> 
> Do you have any plants in the tank?


 Thanks for the reply!

No plants 2 48" Beamworks reef bright LEDs I do get "good algae" until the Tropheus start munching too much, but it always grows back, nice thin layer on some rocks. The Cyano seems to only show up on one side of the tank on the substrate. I am going to try taping over a few of the LEDs on that side and see if it goes away. Tough thing is last time I had it, I shut the lights off for 5/6 days with minimal feedings and it was still there when I turned the lights back on. I have been doing one ta two water changes a week around 40%. Substrate cleanings once a week. Nitrates in the 10 to 15 range if that. I am going to get a phosphate test kit. Never had one so I am curious what the level might be? Don't think it's the food? Been feeding yourfishstuff Supergreen veggievore flake and some NLS. Worse case I will hit it again with the erythromycin and get rid of it then knock the lighting down.


----------



## DJRansome (Oct 29, 2005)

I don't have any problem with full LEDs...if the bulbs are new then I would rule out lighting.

What about circulation in just that one spot?

Good idea to test phosphate, but I don't have any yet still get cyanobacteria from time to time. Languishing plants (including algae) is usually the cause for me, or that one tank with the old bulbs.


----------



## Deeda (Oct 12, 2012)

All the info on forums that I frequent usually list the following possible causes for cyanobacteria outbreaks:

Low water flow or circulation in the tank
Low nitrates <20ppm, usually in a planted tank. I don't know if this also applies to non-planted but assume the live plants are using the nitrate.
Excess organic loading, either in the substrate or filter
Old light bulbs are often suggested as a culprit

I have this problem on a rack of tanks that have fluorescent bulbs older than 2 years and are using HMF sponge filters which don't have a lot of flow when compared to a power or canister filter. I used the Erythromycin on 3 of them and it knocked it right down but need to buy more for the rest of the tanks.


----------



## JimA (Nov 7, 2009)

Thanks! I did a good cleaning of the tank and moved a couple of power heads around will see if that makes a difference? There are still some chunks of the green stuff around my guess is they will multiply. So may end up getting the antibiotics to kill it. It's weird stuff! Also going to cut back on the feedings to a smaller amount once a day.


----------



## JimA (Nov 7, 2009)

I moved a power head yesterday pointing down and across the substrate. This morning there was a nice, call it a divot in the sand where the power head was pointed. Fast forward to tonight, I get home and there is a patch of blue/green cyano spot dead center of the divot where the power head is pointing.  Less than 8 hrs so I can scratch that off the fix it page. :lol: The low nitrate theory is intriguing, but hard to believe with my tank? I didn't get a chance to get a phosphate test kit yet.


----------



## DJRansome (Oct 29, 2005)

The only reason low nitrates is a problem is when you have plants. Nitrates are their fertilizer...when nitrates are low the plant languish and leak fluids that the cyanobacteria thrive on.

Maybe the reef LEDs are too much for a tank without plants?


----------



## JimA (Nov 7, 2009)

Scratch nitrates then, I have no plants. Would agree with the lights, but I have had them for a couple of years maybe even 3. First outbreak was 6 months ago. Still I am going to cover some of the lenses with black tape.


----------



## wortel87 (Apr 15, 2014)

Absolutely dont scratch the nitrates!

I suggest. Add a phosfat killer in the filter. Up nitrates to 20. Take out all the rocks and clean the substrate everywhere. Reduce the lights to 6 hours a day. Every water chance clean the substrate really well.

Then add a medication for blue green algea specifically. If you kill your filter the chance of them comming back is allot higher.

If they are gone. After a few week raise the light durating 30 min every week. Or every other week.


----------



## JimA (Nov 7, 2009)

wortel87 said:


> Absolutely dont scratch the nitrates!
> 
> I suggest. Add a phosfat killer in the filter. Up nitrates to 20. Take out all the rocks and clean the substrate everywhere. Reduce the lights to 6 hours a day. Every water chance clean the substrate really well.
> 
> ...


 Appreciate the feed back there! But it's not like I have a massive outbreak of the stuff. :wink: Today I cleaned the 3 canister filters I have, which were not bad. Did another good substrate vacuuming and added one dose of erythromycin. I am gone for 4 days here through the holidays and will leave the lights off and no feedings. I also covered several of the LED lenses with black tape to cut the light down today and tomorrow then blacked out for the extended weekend. The antibiotics are already working so will see how it looks when I get back.

Thanks for the help everyone! Will update on Monday. Merry Christmas to all!


----------



## BC in SK (Aug 11, 2012)

You might find some use full info in this thread (?). http://www.cichlid-forum.com/phpBB/viewtopic.php?f=47&t=347481
From my perspective, asking what 'causes' algae is usually the wrong question. It would be like some one with a planted tank asking what causes the plants? The aquarist put it there. Same thing with the algae, one way or another, with fish or water, it was put there. Algae comes from algae....and under many conditions, it will take off and thrive.
Nor do I think it all that use full to exclude cyanobacteria from the very, very general term "algae". Red algae, brown algae, green algae.......all very different from each other and all fairly general terms in themselves ( just as an example, would most people view diatoms and giant kelp as all that similar because both are classified as brown algae?)


----------

