Questions - Need some input

Was doing research on my cyano problem and found some articles by Melev which of course led me here. I have been battling cyano for a few weeks now and I have been pretty frustrated. I have siphoned, cut way back on feedings, increased water changes, and added GFO. But no luck so far. Of course parameters are all in line which tells me nothing. So I was looking at either Chemiclean or doing the 3 day blackout. Was leaning toward the blackout, although I saw a comment about bubble corals and I have ...