GLB SuperSonic is a multi-use product that disinfects, sanitizes, clarifies, prevents algae and keeps your pool healthy and safe. SuperSonic is very easy to use, super convenient, and works will all pool surfaces. This product does not contain cyanuric acid and leaves no residue either. It is recommended to use SuperSonic during the evening or “off-hours” while the filter is running. Broadcast the product over a wide area in the pool on the deep side. GLB pool care products have been keeping water healthy and optimized since 1956 while remaining on the cutting edge of the industry.