Description
This product is used to increase the calcium hardness in spas and hot tubs with low levels of hardness. Low hardness levels will etch plaster and corrode equipment. Before adding this product, test the water with a calcium hardness test kit or ask your local spa dealer. The ideal hardness level is 200-400 ppm (parts per million). 1 ounce of product per 500 gallons increases hardness by about 10 ppm. 1. Determine amount of product to be added using a calcium hardness test kit. 2. Pour proper amount into spa or hot tub with equipment turned ON. 3. Run filter for 1-2 hours. 4. Water may be retested in 20 minutes.