CHLORINE SANITIZER FOR SPAS AND HOT TUBS. HASA HI-TEMP SPA-GARD sanitizes and oxidizes the spa water and brings new sparkle to dull water caused by the buildup of organic waste. It also kills harmful bacteria in the spa water. HASA HI-TEMP SPA-GARD has an almost neutral pH, making it the perfect choice for normal sanitizing and shocking of your spa water. Sodium Di-Chlor-Granular Chlorine Sanitizer for Spas and Hot Tubs.