Blue-green algae

[Morganna]

Yeah, I'm sure everyone is probably tired of hearing about another cyanobacteria problem, but my situation is a little different.
So, I restarted the tank up in august, and went fishless till just a few weeks ago. All I have is a ton of plants and driftwood, as well as the new addition of shrimp. Anyway, some cyanobacteria is growing in the tank, but only on my portions of Christmas moss, nowhere else.
But I do want the stuff gone, as it is hindering the growth of my moss, and I know that the shrimp aren't going to eat it (and I don't blame them).
I wanted to know what kind of route I could take that would be safe for the shrimp. I have a product labeled as a blue-green algae stain remover, but I don't know if it is shrimp safe. I read somewhere that you could a hydrogen peroxide dip to remove the blue-green algae, but I don't know if it would kill the moss. The moss portions are attached to rocks that can be removed from the tank.

So I'm just looking for a shrimp safe solution to getting rid of the cyanobacteria.
Thanks!
-Morganna

 

[TNG]

As far as I know, blue green algae thrive in strong light in warm and stagnant water. They are everywhere here in summer in the wetlands where the flow is restricted. Have you tried placing an air stone where the problem is? It could take a couple of weeks before they disappear though.

 

[Uberhoust]

To build on @TNG comments I have been having an issue with cyanobacteria as well and found that increasing the current in the tank helped quite a bit but it is still present. Removed a spray bar and replaced it with a single nozzle last week and the change was pretty dramatic.

Last night during my weekly water change I also severely pruned my plants, especially the jungle val. I hope this will help.

I don't know how well crustaceans will handle hydrogen peroxide, but in the past I have tried a total black out for 5 days and that was very effective and kept the bacteria down for a number of months afterwards, but this did set back my various Amazon Swords.

 

[Byron]

Cyanobacteria in an aquarium is caused by high nutrients in the presence of light. In this regard, it is much the same as "problem" algae. In a new tank, you have another factor, the imbalance in the biological system that does in time settle out (unless the aquarist interferes somehow, which can make things much worse).

With no fish present, the organics should be minimal, but this is another case where they can be very high in the tap water. Bacterial blooms for example can occur in new tanks due to the waste bacteria reproducing and feeding on the dissolved organics in the tap water. Another member also noted that these can be much higher during certain seasons, especially summer.

The resolution is never to add any chemical or substance, as these will invariably harm plants, or fish, or shrimp, or bacteria. Fix the cause and it should be over.

 

[Morganna]

Thanks for everyone's thoughts so far!
It is filtered with a simple sponge filter, and a pothos helps. I don't have the equipment to put an air stone near the affected areas unfortunately, though I liked the idea.
I'm thinking about removing the portions of moss and doing a hydrogen peroxide dip outside of the aquarium. If that doesn't work, then I might try the blackout idea.
Thanks again, will make sure to update with results!

 

[Morganna]

Unfortunately I'm still battling the BGA.
I'm at the point where I'm removing the moss and pulling it off by hand, then putting it back in the tank in a separate spot where it isn't touching anything with cyanobacteria on it. It has also spread to my other plants, and it's a pain to try and remove.
I am scared to try and chemically kill the BGA because of my shrimp, and I don't want to kill my plants by doing a blackout.
I feel like I read somewhere that BGA can appear because of nutrient deficiencies, and I wonder if maybe some fertilizers might at least slow the growth? (I know I could be very wrong, but I wanted to know).
Any thought or advice is much appreciated.

 

[Uberhoust]

First off, cyanobacteria is pretty mobile. The stuff I am fighting appears to be a species of Oscillatoria, based on microscopic comparison to images of the genus online and also because I can see it move in the petri dish under the microscope. The point is I can watch it move and after I clean the tank within 24 hours it re-colonizes the areas I specifically removed it from, so moving your plants to an area not colonized might help with the plants, but if you are moving them to where the bacteria was, but now cleaned, you might end up with the bacteria on your plants again because the bacteria move back to an ideal location.

Right now if I siphon up the bacteria it takes about a week to fully come back. The nitrates in my tank are running between 2.5 ppm and 5 ppm and I know I am not overfeeding my fish. Two weeks ago I added some fertilizer tabs (Seachem) these have not increased nor decreased the bacteria. Four weeks ago I removed all dead or dying vegetative matter from the tank and increased the flow on the filter, this seems to help a bit, but it is hard to tell.

If the concept of nitrogen depletion can cause the cyanobacteria to spread, due to it being able to outcompete for this nutrient, then having more nitrogen available to the plants might help. Nitrate in a fertilizer, more fish (my tank is lightly stocked), or possibly more food to the fish will all raise the level of available nitrates, allowing the plants to compete better with the bacteria, might be the solution. In the literature I find inferences to this concept but little actual study of this one factor. The next step for me, is to allow the nitrates to rise to say 15ppm and see if that improves things. There is the possibility that adding more nitrogen might cause more bacteria, which is why I have been waiting to see if other treats work first.

I would seriously considering adding more fertilizers if I was in your situation, but it would be truly a test and I would like to know your results. I will be doing the same soon if nothing in my tank changes in regards to the cyanobacteria.

 

[Morganna]

A wonderful response @Uberhoust, and I am grateful for your opinion on this matter.
Unfortunately it might be a couple of weeks before I can get my hands on some fertilizer, but when I do and start trying that, I will make sure to share results.
Thankfully the cyanobacteria isn't really on my sand, because I make to clean that pretty good. It's just on the plants with quite the grip.
Thanks y'all.

 

[Uberhoust]

In my case the bacteria is on the sand. I don't expect my CB issue to clear up fast. My fish are still happy.

 

[StevenF]

Cyanobacteria in an aquarium is caused by high nutrients in the presence of light. In this regard, it is much the same as "problem" algae. In a new tank, you have another factor, the imbalance in the biological system that does in time settle out (unless the aquarist interferes somehow, which can make things much worse).

I use 100% RO water and make my own nutrients. And recently I was able to eliminate it from my tank. Cyanobacteria appears to prefer water with deficient levels of micro nuents. I disappeared once that deficiency was corrected.. So it is not caused by high nutrient levels. Lighting only controls the consumption of nutrients by plants. Lowering light can increase nutrient levels. I didn't touch my light levels before and after adding the correcting the micro issue. High macro nutrient levels din't encourage the growth as long as you have sufficient micros.

Micro levels in my tank are 0.05ppm iron (Fe), 0.025ppm manganese (Mn), 0.01ppm Boron (B) and zinc (Zn), and 0.003ppm copper (Cu). and 0.005ppm Molybdenum (Mo) and Nicke Ni)..Macro nutrient levels had no effect. Most micro fertilizers have of my zinc level, less than 0.001ppm of Copper, and No Nickel. Also the ingredients are not very stable Making it hard to get things right.