REMOVES METALIC STAINS AND SCALING AND REDUCES PHOSPHATESFast-acting and long-lasting sequestrant helps remove and protect all pool finishes from stains and scale. Helps control plaster dust in start-ups. Highly effective in all pool sanitizer systems including salt chlorine generators. Cleans and helps prevent scaling of salt cells. Contain Phos-Stop Plus will not yield phosphates reduces existing phosphates in pool water.