Spa Boss Brominating Granular is a high-quality 1-step bromine sanitizer for hot tubs. Bromine granules are quick dissolving, soluble and provide effective bromine sanitization. Bromine is an alternative to Chlorine. Bromine is can be used over a wider range of pH levels and is more forgiving of many water balance issues. The bromine level in your spa should be maintained between 3-5ppm.