Potassium monopersulfate (Spa Shock) should be added to spa water after every use to immediately oxidize and eliminate organic contaminants introduced by bathers. Public spas used every day may need to oxidize daily with potassium monopersulfate. Regular oxidation with potassium monopersulfate promotes maximum sanitizer efficiency. Since it contains no chlorine, it will not produce combined chlorine or generate chloramine odors.Read More