HTH™ Calcium Up is a pool hardness increaser that raises calcium hardness back into the recommended 200-400 ppm range. It prevents corrosive water from damaging your pool.
Prevents soft water from etching plaster and damaging surfaces
Target range: 200-400 ppm
Fast-dissolving granules broadcast easily with pump running
Never add more than 10 lbs per 10,000 gallons at one time
