@vetteguy53081 - I'm curious about the phrase nutrient imbalance. I've seen it used a lot in relation to cyano, but I'm not sure what it means. Are we talking nitrate and/or phosphate levels are simply too high, or that one is out of whack compared to the other?
The back story:
I've been fighting a cyano outbreak for a few weeks now. I'm not sure what all the causes are in my situation, but I believe the last straw was that I let me gyres impellers get dirty reducing the flow. That has been fixed, and the gyres get disassembled and cleaned monthly now. I've also bumped the flow through the return pump up a bit just for good measure.
I'm still pulling quite a bit of cyano out of the tank, but everything else seems pretty good. My nitrates are usually 10-20ppm and my phosphates are usually 0.15-0.2ppm. I've been slowly lowering phosphates since they are a bit higher than "generally recommended", but at this point I am guessing.