CalTreat revolutionizes how you balance your pool by lowering Calcium HardnessCalTreat is a revolutionary formula that will effectively lower your swimming pool’s calcium hardness by 200-400 ppm. It is the only effective calcium hardness reducer on the market. Traditionally, lowering calcium hardness involved partially draining and refilling your pool level. This was a costly method, and for many who live in areas with hard water is ineffective. CalTreat changes this by removing calcium hardness from your water using your filtration system.