I added a second Maxspect Gyre 280 pump on the other side of the tank and flow overall is very good now. Could be a random coincidence but I started using Selcon every day with feeding back in April and the Cyano started right around then as well. Don't think it's related but there is at least one post on Reef2Reef where someone had Cyano start when adding Selcon and then go away when they stopped so worth a try at least. Another thing I am going to try is changing the filter sock every Monday and Thursday vs just every Thursday. But yeah, the Cyano in my tank is VERY aggressive