Bio-Active is an all-natural and ultra-powerful solution to reducing high levels of cyanuric acid (stabilizer) levels in swimming pools. Cyanuric acid build-up comes from over chlorinating with tablets, sticks, or granular chlorine. These products contain up to 55% cyanuric acid which helps block the sun's UV rays and effectively makes your chlorine last longer. When the level builds to 100 PPM, pool owners start to struggle with water clarity and chlorine lock. Up until now, the only solution was to drain water and refill. Bio-Active solves that problem, especially for pool owners in drought-stricken areas with water restrictions. 1 - 8oz. pouch treats 25,000 gallons and can effectively reduce CYA by 50%!