cyanobacteria is a true eye sore. there are some manufacturers that claim they have the cure but i haven't tried any of them. what are you using on your tank? filtration and protein skimmer wise? cyanobacteria is caused by excessive nutrients in your tank, poor water conditions, death of fish, fish excrement, and just waste in general. have you siphoned it out yet? that's your first step, many inverts will eat it and break it up by walking on or over it but it difficult for them to keep up with it if it isn't going away. the scarlet hermits, the emerald crabs, the red legs, the blue legs, they will all helpwith it but you need to find the source first and it all starts with your water conditions. how many inches of fish do you have in your tank and are you using a protein skimmer?