cyano

[DEAD_BY_DAWN]

Just do the water change after treatment and everything will be fine,i have never heard of any negative effects and we sell alot of it.

[Bartman]

I fought Cyano in my nano for ages to no avail. I tried Chemiclean once about 8 months ago and I haven't seen any cyano since then. Everything in the tank stayed very happy (except the cyano). Just turn off your skimmer for a day or two as it will overflow like crazy and aerate the tank by some other means.