GSA getting under my skin

Hi,

If GSA means green slime algae, I had a problem with this and the problem was too much c02. I cut the c02 down by 2/3 of what it was, and within a few days it was gone.

Won't guarantee this is the problem, but is worth looking at.

 

Hi,
It's generally agreed that Green Spot Algae is induced by either low PO4, low/unstable CO2, or both. I can't imagine that lowering the CO2 concentration can do the plants any good at all. You normally want this value to be as high as possible (without stressing fauna) and to be as consistent as possible. Therefore I would hesitate to suggest CO2 reduction as a cure for any algae, including slime. There are so many variables in the tank that one has to be careful to avoid drawing conclusions based on circumstantial evidence alone. I doubt seriously that you could induce slime or spot algae by increasing stable CO2 levels by 2/3rds but you might be able to induce it by continually varying the levels. The disappearance of the slime algae was most likely cause by some other factor which occurred coincident with the reduction of CO2.

Deleting PO4 is always an extraordinarily bad idea as this can result in stunted growth and other algae problems. It would have been better to increase all nutrients for that three week period. Then, work on stabilizing the CO2 using a drop checker with 4dkH water to monitor the levels. DIY CO2 is notorious for it's instability, but it could also be that there are problems with the regulator, the diffuser or with circulation.

Cheers,