I have a 65 gal hexagon I have had it set up for african ciclids since october. Over christmas I had a major algea bloom and since then I still cant get it to clear up. I am running a 50gal emperor 250 marineland and a 30-40 gal whisper over the back filters. I have 2 bubble stone in the far corners as it is a deep tank and I want to be sure there is adequate O2 supply. The tank is in a corner that gets the least amount of sunlight and absolutly no direct sunlight. I have about 30 fish more than half are under 1 in some are about 2 inches and only 2 that are full grown. Decorations are all riverbed rock that was all cleaned and soaked before I put it in and then boiled over christmas when I panaked and cleaned out the tank completly. I also have one large carved red rainbow rock and several fake plants as the live ones get destroyed. amonia levels stay at 0 nitrite stays at 0 nitrate less than 5.0 ph stays firm at 8.2 and my KH around 200 but i have seen it get really high like over 400! I have tried changing the filters without changing the bio filter I have tried cleaning them both I have been doing 20-40% water changes every couple days I have tried covering the tank to light for 2 days nothing seems to help clear it up at all! I do not know what else to try! I would love to post a picture if anyone could tell me how.