This is a 4 pound container of calcium hardness increaser which will raise the total the calcium hardness in your swimming pool water. This calcium di-chloride product is in granular form. For most pools, calcium hardness levels should be maintained between 200 and 400 ppm.Active Ingredient of the Harness Increaser: 100% Calcium Di-Chloride.Directions for Adding Harness Increaser to Your Swimming Pool:If calcium levels are low, add this product directly to the pool water. Always apply with the circulation system operating. Brush any undissolved particles from the surface. Add 1.25 pounds per 10,000 gallons of water to increase hardness levels 10 ppm. Avoid increasing hardness more than 30 ppm every couple hours. Pool use may resume 15 minutes after the product has fully dissolved in the pool.
