Clorox Spa® Antifoam prevents and eliminates foam in spas and hot tubs. A foamy spa is one of the most common issues that spa owners experience. A little foam is okay, but too much gets irritating and causes concern. Use the Clorox Spa® Test Strips to test your spa once or twice a week. Factors such as pH can change quickly, so test regularly. Maintain a pH balance of 7.2-7.6 and 3-6 ppm of bromine. Drain, clean, and refill your spa every 90 days.