I have a 90 gallon aquarium with a 20 gallon sump and I have a 36 watt UV on it running at about 400-500gph. The UV cleared the tank up once before, so i know it works for my tank. I put in a bunch of coral and the tank started to get murky with what i think was a bacteria bloom. After a water change the tank cleared up for a day, but the tank soon started to turn green. I turned the white lights out and am just running blue (4 white, 4 blue T5). Do y'all have any clue how i can fix this?
My nitrates are 3ppm and i think lowering and my phosphate is undetectable using a salifert.
Any help would be appreciated

My nitrates are 3ppm and i think lowering and my phosphate is undetectable using a salifert.
Any help would be appreciated



