SpaBoss Cal Rise is the effective way to increase the Calcium Hardness of your spa or hot tub's water. The ideal range of hardness is between 150-275 ppm. Cal rise is granular and should be diluted before adding to water. Cal rise is pH neutral.

A low calcium hardness causes corrosive water and staining of surfaces. A high calcium hardness causes scaling of heating pipes, cloudy water and staining of spa