Dissolves quickly and remove organic contaminants that cause dull, cloudy water and other problems. Kills and controls green, black and mustard algae. Also kills bacteria. Reduces chlorine odor and eye irritation. Improves filter performance. Won’t impact pH. Treat and swim in 15 min.6-in-1 shock with algae-killing crystalsKills and controls green, black and mustard algaeKills bacteriaClears cloudy water and removes swimmer contaminants such as body oils, sweat, lotions and urineReduces chlorine odor and eye irritationImproves filter performanceWon’t impact pHTreat and swim in 15 mins, test-free chlorine before swimming to ensure it does not exceed 4 ppm