Spa Essentials Spa Shock Oxidizer 7# Spa Essentials Spa Shock Oxidizer 7# Non-Chlorine Spa or Hot Tub Shock Shock Oxidizer is compatible with chlorine and bromine sanitizing systems, and will improve the overall health and appearance of your spa or hot tub. 1oz per 300 Gallons of Spa or Hot Tub Water Eliminates any organic material from the water while significantly cleaning up the water to crystal clear quality