I've tried a product called
Red Slime Remover and it's extremely effective in removing the cyanobacteria you're facing... It is a yellow powder and when added to the tank's water, the skimmer absolutely goes berserk... so prepare for very dry-skim and tune the water level in your skimmer to the lowest if possible... If the skimmer overflows, you have no choice but to off it, after 2-3days, the cyano clears up!! Like magic!! I haven't detected any side-effects after administering it twice to my old 90 gallon... I didn't lose any fish or corals and the product IMHO is really effective!
