HTH Super Shock Treatment with Test Strips is an all-in-1 calcium hypochlorite (Cal Hypo) pool shock designed to restore crystal-clear water in 24 hours. This Costco value pack includes 15 individual one-pound bags of shock treatment plus 15 pool test strips to keep your swimming pool clean, safe, and properly balanced all season.

Each one-pound bag rapidly boosts chlorine levels, kills bacteria, and destroys algae without adding cyanuric acid (CYA), which prevents the chlorine lock that can occur with stabilized shock products. One bag is formulated to treat up to 13,500 gallons of pool water. The formula also helps prevent stains and scale buildup, improves filtration efficiency, and softens water for a visibly brilliant sparkle. A built-in Visible Blue Action feature lets you see the product working as it disperses.

Compatible with all swimming pool types including vinyl-lined pools and saltwater systems, this shock treatment will not fade pool liners. For best results, add directly to pool water or the skimmer following the on-pack dosage instructions based on pool volume. Use weekly as part of your regular pool care routine to keep free available chlorine levels between 1 and 4 ppm. The included HTH 6-Way Test Strips allow you to test and balance your water twice weekly for optimal swimming conditions.