About This Item Relax into fresh clean water with this easy to use non chlorine shock oxidizer. HTH Spa Non chlorine Shock Oxidizer effectively reduces odor causing ammonia and chloramines resulting in clear clean and healthy water. This product is great for bromine and chlorine systems. For best results use HTH Spa Non chlorine Shock Oxidizer as part of your regular HTH Spa care routine. How To Use HTH Spa Non chlorine Shock Oxidizer With the filtration system on apply 2 ounces 4 tablespoons of HTH Spa Non chlorine Shock Oxidizer for every 250 gallons of water. With the spa cover off circulate your spa water for 15 minutes. About HTH Spa For generations, HTH has been leading the way in smart spa care. We do the chemistry so you can just take it easy. From the very first day you open your spa HTH is here to help maintain and problem solve. Our complete range of simple to use no nonsense products empower you to balance sanitize and treat your spa it is everything you need and nothing you do not. There is nothing more relaxing than taking it easy in sparkling clean water. With HTH your spa is always ready when you are.