Did u ever find out the problem.I have the same issues and have spend thousands of dollars trying to fix this?Kaye in Illinois wrote:My neighbor has had a recurring problem for 5 years with gray clouds forming as you said. Now our pool has it this year. She has taken samples in to many pool supply stores and noones seems to know what it is. It seems to be floating in clouds at the bottom of the pool and can be vacumed up but disipates if you stir it. After you vacuum it clean it reappears the next day or later that day in the same places. We have shocked and clarified and vacumed to waste. With no luck, she has had a pro come out and drained her pool scrubbed the liner replaced the filter. Tonight with only about 18 inches of new water we could see it already returning on the floor of her pool. HELP! If anyone reads this and has an answer we would love some help. Ours showed up when we opened the pool this year. Her started at the end of the first year they had their pool and has never gone away. Our water tests correct for all the chemical levels. The pool places said that algae would be adhered to the liner and would not be suspended in the water in cloud like formations and be able to vacume it up. We don't know if it's algae or a fungus or if it's dangerous. We now fear we will be doomed as they are and never be able to get rid of this problem. Somewhere I read there are resistant algaes and fungi and that a chlorine/bromine combo might work.