I need help, please. What kind of algae is this? I've been in the hobby for many years, but haven't seen anything like it before. It starts neon green on the Aragonite substrate, turns red, like cyano, then dark purple. It only appears in the front of the tank. I can't seem to get it under control. It's very aggressive and comes back quickly. I've tried replacing the lights and the substrate. I've tried Chemiclean for red cyanobacteria. I've tried Algae-fix Marine. I've tried NoPox. Phosphates and nitrites are 0, nitrates are 10, ph 8.2. Ive got good water flow, sump, refugium and a protein skimmer. 130 gallon tank with 40 pounds of live rock, well established for 8 years. This is the first time I've ever had a problem getting rid of algae. Please advise.