Yes i have the same problem. I have two decorator urchins for hair algae, they work really well. But for cyano, there isnt much that will eat it. Generally it grows on hair algae which it feeds off of ive noticed. Or over a sand bed with rotting organics which it feeds off of. You could dose an antibiotic which would kill it. But i prefer to get to the source. Urchins for algae and clean the sand with a gravel vac. Most people use chemiclean iirc for cyanobacteria.I have an UV sterilizer on the tank. At this moment I dont have dinos, I think the UV did a good job on that part, but doesnt help with the other algae problems.