HTH Chlorinating Tabs are a simple, convenient way to keep your pool water clean and clear. Simply place tab(s) into the skimmer basket, floater or feeder to sanitize and protect your pool water from algae and bacteria. They are sun protected and designed to dissolve slowly, giving your pool a steady source of available chlorine for up to one week. HTH Chlorinating Tabs are great for all pool types, including small pools, pop-up and above-ground pools, vinyl-lined pools as well as salt water systems. Follow the on-pack instructions to place tab(s) in your swimming pool feeder, floater or skimmer. The amount of tabs you use depends on your pool size. Do not add tabs directly to the pool as this can cause damage to pool surfaces. Repeat every week or as often as needed to maintain a chlorine residual of 1-4 ppm.Protect your swimming pool and enjoy clean, clear water with these easy-to-use chlorine-based tabs.Kills algae and bacteria. Use in floater, feeder or skimmer basket.Tabs last for up to 1 week. Easy to use.Chlorine Tabs keep water clear while protecting against bacteria, algae and other organisms.Sun protected for longer chlorine life, Chlorine Tabs dissolve slowly and last up to one week.This product is great for all pool types, including salt water systems. Use 1 tabs for above ground pools, 3 tabs for inground pools.For best results, use HTH 6-Way Test Strips twice weekly to test and balance your swimming pool water and keep chlorine levels between 1 and 4 ppm.