I was using 5 6025s in a 50 gallon tank. Tank contains no fish, just various montipora and pavona, and a few brittle stars that never leave the rock. Are the covers on the nanostreams there only to protect the fish? I tried removing the covers and I had to remove a powerhead, and move the other 4 deeper into the tank to prevent water from spraying out. Even so, the tank looks like a cloudy whirlpool. Is it ok to run the 6025s like this? If it is no need to upgrade.