HTH Shock! treatment, 6 bags 13.3 oz each, is an effective, multi-purpose product that sanitizes, clarifies, helps prevent algae and shock treats your pool. It is convenient, easy-to-use and won’t over-stabilize your pool. HTH Shock! treatment is the original swimming pool shock designed to boost chlorine levels and kill bacteria and algae for a clean, clear pool. This pool shock is great for all pool types and won’t fade your pool liner. Test and apply shock treatment directly to your swimming pool every week to keep chlorine levels between 1 and 4 ppm for healthy swimming conditions.Increases the chlorine level in swimming pool waterKills bacteria and algae in swimming poolsShock treatment effective for all swimming pool types including pools with liners and gunite pools and salt water pool systemsWon’t fade linersTest pool water and shock weekly to keep chlorine levels between 1 and 4 ppm