Clorox Pool&Spa Crazy Clarifier helps you maintain a crystal clear pool all summer! This pool clarifier is our most powerful formula. It works by combining small contaminants in your pool into larger ones so your filter can take them out of the water. If your pool looked a bit cloudy, this will help restore it to the blue, beautiful look you expect from your pool. Even if the water didn’t look too cloudy, you’ll still notice a difference! Just apply this clarifier for pools once a week per the use directions. We recommend doing it at the same time as your normal pool maintenance, such as when you test with Multi-Use Smart Strips or apply your shock.