Sadly, water changes don't really mean good water quality. I do anywhere from 5-9 9% water changes a day, but my tank would still be in a bad shape without good bio-filtration. And if I ever got a bit of Windex in the tank by accident, goodbye fish. There's a million things that could go wrong with water quality, and I'd be willing to bet that halofishboy is right in some aspect. Have you ever tested your water? And if you have, what were the results? PH, GH, Nirates, etc?
