Shocking the pool water will burn off additional contaminants deposited in the water through rains, winds and organic bather waste. Formula “O” is an EPA registered, nonchlorine, blended powder that is added to the water weekly and combines most of the typical ancillary chemicals (shock, algaecide, clarifier, stain and scale prevention) into one easy weekly treatment rather than adding multiple chemicals separately. Formula “O” is so gentle that you can swim in 15 minutes after use. No need to wait for hours or days for the pool to become safe after shocking with chlorine.
In the end, the ability to generate ozone, peroxide and hydroxyl radicals along with a weekly shock using an Oxidizing Shock blend works far better than anything else we tested for water clarity, freshness, and safety in residential pools.