<a href=showthread.php?s=&postid=11024447#post11024447 target=_blank>Originally posted</a> by Coralfreak
Make sure your skimmer is running the best it can, clean it up and then set it to run a little on the wet side. I have found that wet skimming can sometimes knock down cyano outbreaks. I assume your are using RO/DI water for both water changes and top off?? Make sure it has a TDS of 0.
Have you tested for PO4? Are you using anything to control phosphates?