BENEFITS: Prevents pH drift USE: Use this product each time you refill your spa with water; One bottle treats up to 500 gallons of water COMPATIBILITY: Works with chlorine, bromine, ozone and mineral purification systems; Designed for use in hard water areas (calcium levels above 150 ppm) FEATURES: Fast Dissolving, easy to use granular formula; INCLUDES: One 3.25-lb bottle of Leisure Time pH Balance Plus Designed for use in hard water areas Fast dissolving