What would make water turn cloudy in a fishtank?
If you cleaned your tank a little too well, then you might be experience what is known as bacterial bloom. Tanks should never be completely cleaned. Gravel should be vacuumed, not rinsed, water should be replaced in portions of 50% max (preferably more often at 25%), and the filter media should never be cleaned or replaced all at once, unless you have a bio-wheel to support bacteria. In the mean time, just do frequent small water changes and let the tank mature again – the cloudiness will go away on its own with patience. Aside from that issue, overfeeding is the most common reason for cloudy tanks. One must make sure all the food is eaten and feed the fish reasonable amounts – there is no need to stuff the fish to the gills every feeding – this is unhealthy to tank and fish. If the cloudiness is green, then the above mentioned algaebloom (suspended algae) would be correct.
