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It is hard to say what is causing the water to turn cloudy without knowing the history of the tank. Can you describe the age, filtration, livestock, size and current water parameters? If this is a new tank, cloudy water is common as the substrate settles. "White haze" can also mean an excessive NH3
level in the water. This is very toxic to livestock. Does the water smell foul? It is possible that you distrupted the biological filtration of the tank causing a mini-cycle. Sorry...more info is needed.Please list NH3