Cyno took out my hammer coral and gonipora, but i treated it with "chemiclean" and I have been living cyno free since then. But when i used it, I turned off my skimmer and UV Sterlizer for 48 hrs and then did 30% water change, and then turned everything back on. Its been no cyno since then. Cyno outbreak happened about 3 months ago and I am cyno free since then.