Hydrogen peroxide not killing cyano?

[vdubers]

Good luck with this. I feel your pain and have been battling this myself. Half of the reef is typical cyano and the other half is predominantly spirolina. How does this happen? All on rocks and overflow walls but not on sand. It's been a battle.

Ah no good luck with your battle too it’s a tough one! I will keep this thread updated if/when I eventually beat it totally. On the plus side mine doesn’t seem to impact corals much as long as I blow it away from them regularly.