Super 3” chlorinating tablets keep your pool clean and clear with a 4-in-1 formula that sanitizes pool water and protects against chlorine loss due to sun exposure. This formula includes built-in algae protection and clarifier for an amazing value in DIY pool care. Apply tablets to feeders, floaters or the skimmer basket, adding 1 tablet for every 10, 000 gallons of pool water. Sun protected for longer chlorine life, 3” tablets dissolve slowly and last up to one week. They’re great for all pool types including vinyl-lined pools and saltwater systems. To use: place one tablet in pool feeder, floater or skimmer per 10, 000 gallons of water every week or as often as need to maintain a chlorine residual of 1-4 ppm. Do not add directly to the pool as this can cause damage to pool surfaces. Be sure to run the pump at least 8 to 10 hours per day. Test pH and chlorine levels at least two or three times per week and adjust as needed. HTH Swimming Pool Advanced Chlorine 25-lb 3-in Chlorine Tablets | 42055