I cleaned my filter for the first time two days ago (what a mammoth effort! ) Luckily I had read (here) that I should clean it with aquarium water, since the LFS said tap water! Seemed to go ok, and the water flow is definitely running better. Yesterday though, I noticed that my water seems a little cloudy. What might that be? Levels are Ammonia 0, Nitrites .025, Nitrates 1