Spa Choice 472-3-4011 Spa Chemical to Increase pH Level, 1-Quart Raises the pH level in your spa or hot tub Spa Choice Increase pH is compatible with all sanitizers including bromine, chlorine and biguanide The water in your spa should be maintained at a pH of 7.2-7.8 ppm (parts per million) Downloadable User Guide Available Under Product Information: Technical Specifications