Calcium Chloride Anhydrous Powder Increases Total Hardness of Pool Water Used to Prevent Corrosion in Pools & Hot Tubs Great Value: 1 Gallon of Calcium Chloride Powder Lab-Tested & Certified Manufactured in the USA Calcium Chloride Anhydrous for Pool & Hot Tubs.
Use hand and eye protection when handling. Place water in a mixing bucket, then add in Calcium Chloride. Do NOT put Calcium Chloride in the bucket first.
To increase Calcium Hardness by 2 ppm, add 2 oz of Calcium Chloride for every 1,000 gallons. See label for instructions and warnings.