I have a or should say 2 55g tanks with green/brown algae growth and fish dieing off and very discolored. I have good filtration and water movement(oxygen), hiding places ect... but dont understand. I had double the fish in the tank b4 not by choice and now that they r free and uncrowded i seem to have issues. Any ideas would be great thanks in advance and feel free to ask as many questions as needed.