Shocking the pool on a regular basis is an important element in keeping the pool clear and clean. Swimmers and the environment add wastes to the pool that must be eliminated on a regular basis in order to prevent problems such as algae and cloudy water, SunGuard offers a variety of products to shock the pool. For super clear water, add SunGuard Multi-Shock once a week or as needed. More frequent shocking is needed after rainstorms, heavy bather load, or exceptionally hot weather.