I used Brightwell Razor hair algae remover in my tank due to a lot of green hair algae build up. I believe I should have had a skimmer but didn’t know this as I am new to reef tanks. I have a 60ltr tank with several kenya trees, a racordia, a green polyp and a lovely anemone. I also have a pistol shrimp and goby and a springer damsel and several hermit crabs. My corals are dying or won’t open up but my fish are fine. My tank although better than it was keeps getting brown slimy algae over the gravel and sides. I’ve changed the water many times and the floss. Salinity levels are fine and I have put a phosphorous bag in my filter. Any ideas what I can do?