SpaGuard Spa Shock-Oxidizer - Non Chlorine (7 lb)This non chlorine shock is the ideal oxidizer for spas with an ionizer unit. It makes undesirable compounds disappear. Spa Shock is simple to use just apply directly into your spa water while the pump is circulating. Try Spa Shock in two convenient sizes of 40 oz and 5 lbs. Can be used with chlorinated or brominated spas, does not raise chlorine residual, quick dissolving shock treatment, destroys organic contaminants, non chlorine sanitizer. Product