So I'm having a bad cyano outbreak in my tank. I've had chemi pure elite which contains gfo and it has lowered my.nitrates as I have tested this and I even have cut way back on my feeding as well. Sometimes feed fish every other day now so not as much phosphate breaking down in tank. I have also increased the flow on my power head from 40% to 60%. It's only a 20L so I don't want to blast around my fish or corals and I also have a tidal HOB so there is decent flow through tank. The only thing I haven't tried is lights out because I have corals but I don't know what else to try. How bad of a affect will this have on my corals? My branching hammer and torch are both splitting as of now. Is there any fish or inverts I can add to help? I have blue legged hermit crabs and trochus snails and assassin snails. Any tips?