I have a question or 2 about cyanobacteria. I have 4 tanks, 5 if you include the QT. I treat them all pretty much the same. Only one of them has ever had a problem with cyanobacteria. There are differences. They are all pretty heavily planted tanks (except the QT), but the plants are all pretty much low light plants. Two of the tanks have led plant lights. The one with cyano has just a regular led light. The cyano tank also has eco complete for a substrate. Two of the others have gravel, and one has fluorite. The problem with the cyano is not huge; it does not seem to be thriving, but it won't die either. I have tried blackouts, cutting back on feeding, adding oxygen etc. The tank is not overstocked. I keep saying to myself that it is not really a big problem since it doesn't spread, but it just annoys me. I have read good and bad about using erythromycin to eradicate the pesty problem, but I am afraid of destroying my biofilter. Would like your opinions. Is it possible that the eco complete could be causing this with the built in nutrients?
An Annoying Problem with Cyanobacteria
- Thread starter biondoa
- Start date
I also had a problem with cyanobacteria in only 1 bank of tanks, it had low outpoint bulbs on a shoplight, but received a bit of indirect sunlight for a short time each day.
All other tanks were treated in a similar manner but they were unaffected.
As an experiment, I started using a probiotic (Rid-X) to compete with the cyano in the sump of that bank of tanks.
6/22/13 just before adding Rid-X
A tablespoon of Rid-x was added to a filter sock once per week.
7/2/13
7/27/13
Since that time, after the cyano receded, I have not added Rid-X, but the cyano has not returned.
All other tanks were treated in a similar manner but they were unaffected.
As an experiment, I started using a probiotic (Rid-X) to compete with the cyano in the sump of that bank of tanks.
6/22/13 just before adding Rid-X
A tablespoon of Rid-x was added to a filter sock once per week.
7/2/13
7/27/13
Since that time, after the cyano receded, I have not added Rid-X, but the cyano has not returned.
I think what you can do to avoid the cycle being wiped out and annihilated is to place the filter somewhere else temporarily. Just use a water pump to make sure there is water movement in the tank, so the antibiotic can get around inside the tank. Is there currently fish in the tank? If you do, you can just put them in a 5 gallon bucket temporarily along with the filter media dumped in that has beneficial bacteria, use a small airstone with gentle output for surface ripples to provide some oxygenation, no need to crank it up.. and a small heater if it's cool where you are at. Give them a good water change every now and then making sure the temps from new water is the same, dechlorinated, and wastes levels are low.
**Edit**
Or you can definitely try out Rid-X mentioned by duane. It will for sure, compete against cyano. A safer method! I would recommend it. I have used it before with no ill effects on my fish.
**Edit**
Or you can definitely try out Rid-X mentioned by duane. It will for sure, compete against cyano. A safer method! I would recommend it. I have used it before with no ill effects on my fish.
For me, it's fifty gallons per tablespoon. Works well. What you do is you mix it really well in a container with several cups of clean filtered water, and let the particles settle down completely.. which takes several minutes. But I usually like to wait for about thirty minutes. Then you would carefully pour the mixture in the tank without pouring down the solids from rid-x. Repeat once every week in your case of cyano until they are all fought off. I usually dose once every two weeks.. that said, probiotics are actually great in fish tanks. 
Keeping the sludge down in filters, fighting off bad bacteria, boosts the immune system of fish, water clarity, etc. Research about it. I used it for a while with no problems. Fish are as healthy as they can be. Give it a shot.
Keeping the sludge down in filters, fighting off bad bacteria, boosts the immune system of fish, water clarity, etc. Research about it. I used it for a while with no problems. Fish are as healthy as they can be. Give it a shot.Rid-X, yes, its the same stuff as in septic tanks. Although there are some probiotic products being produced just for aquariums, and aquaculture these days, if you google there are a number.
What they are is bacterial cultures, (specifically produced non-pathogenic ones), that are used to out compete with less desirable bacteria.
The theory is, the selected cultures help control sludge, and may even out populate bacteria such as those that produce hole-in-the-head, or other fish disease causing bacterial phages.
Same as humans take the ones in yogurt to keep healthy populations in our guts.
What they are is bacterial cultures, (specifically produced non-pathogenic ones), that are used to out compete with less desirable bacteria.
The theory is, the selected cultures help control sludge, and may even out populate bacteria such as those that produce hole-in-the-head, or other fish disease causing bacterial phages.
Same as humans take the ones in yogurt to keep healthy populations in our guts.
Thanks for this very interesting info. I did a little googling and found several products made especially for fish tanks. One is from Dr. Tim's Aquatics. I have used his nitrifying bacteria with good success, so maybe I will give this a try. They will have specific directions for fish tank use, which makes me feel a little safer than winging it with the Rid-X.
Wow, nice recommendation, Slappy. Never heard of that product before. Looks like that would work as well. Awesome.
