Cyanobacteria problem.

[pairustwo]

I have a 20 gallon tank
65W CL 8 hours a day.
Flourite substrate
Nitrite 0ppm Ammonia 0ppm and Nitrate 0ppm (really. I think it is because the plants are eating all the Nitrate and I don't fertilize)
I have a Fluval 204 (180 gph) and Aquaclear 30 (150 gph (really?) )filters running.
I have sponges, filter floss and ceramic media in both filters.
My water is really, really clear. And there is a lot of current. Not to say there aren't dead spots but there is a lot of current.
There are lots of water changes happening.
Feeding once every other day.

So my problem is I have this Cyanobacteria problem. It used to be just on a piece of driftwood then it spread to the substrate and plants.
I've tried to scrape brush and vacuum it off and up which got rid of most of it which was vacuumed and filtered, but now there are many more small patches all over the place that are starting to grow.

How can I get rid of it?
Has anyone tried erythromycin?
I have read the articles section here.
help?
Pairustwo.

 

[rich311k]

The reason you have it is the 0 nitrate level. Erythro will do the trick but you may want to try a blackout and then adding some ferts first. I think of the antibiotic as a final resort.

 

[pairustwo]

The reason you have it is the 0 nitrate level.

How does that work?
From the AA article

As mentioned previously, it is caused by excess organics in a system. This can be brought on by excess feeding, overstocking, lack of filtration, infrequent water changing or from the excess nutrients from cycling a new system. Also, because it is photosynthetic, long light cycles encourage growth.

Which I thought was weird because it doesn't really describe my tank at all.

 

[rich311k]

I am not sure of the why. I do know that if nitrates bottom out in a planted tank the cyano will flourish. I have had to deal with it myself. Algae will flourish in conditions not favorable to plants. Different ones like different things. It is albout a goob balance of nutrients and CO2.

I am going to move this to planted since you have an algae problem in a planted aquarium.

 

[greenmaji]

the difference in dignosis is fish only vs. planted tank.. water chemistry is completly different for planted.