I have a 8000 gallon water tank that has always had pristine clear water. I have a brass float valve at the top input to the tank. Someone put an aluminum ladder in the tank (15 ft deep tank) and after who knows how long, the ladder was encrusted with a white gooey powder and the water turned milky. what happened? Main question is IS the water safe to drink or how do I get rid of whatever is in there.