The tank has been up for about 9 months never had the cloudy until it got an alge bloom got rid of that with a diatom filter and my water has been cloudy since..I have been doing water changes 2X week. After the water change the tank is still cloudy but about 4 days after the change the tank gets a little better and stays that way for 2 days.Then goes back to being cloudy. I have a protine skimmer but that is no help. The tank is a 40 gal. breeder i have 2 porc. puffers, a pink tail trigger ,black banded trigger, lion fish, and a snowflake eel could it be to many fish, or what they eat brime and krill???