HTH 3" Chlorine Tablets are slow-dissolving, multi-action pool sanitizing tablets designed for all pool types, including vinyl-lined pools and saltwater systems. Each tablet delivers up to one week of continuous chlorination, sanitizing pool water, clarifying it, and protecting pool surfaces and equipment from stains and scale buildup.

Each tablet treats approximately 10,000 gallons of water and should be placed in a floater, automatic feeder, or skimmer basket — never added directly to the pool surface, as this can cause damage. Replace tablets weekly or as needed to maintain a chlorine residual of 1–4 ppm for safe, clean swimming conditions. The slow-dissolving, sun-protected formula extends chlorine life and reduces the frequency of maintenance required.

This large-format Costco package contains approximately 45 pounds of tablets, offering excellent value for pool owners who want reliable, long-lasting sanitization throughout the swim season. Compatible with the HTH Test to Swim mobile app for guided water care and maintenance tracking.