Directions for use: Read entire label before using 1. Test spa water for calcium hardness level 2. Compare test results to chart below to determine appropriate amount of Spa Calcium Hardness Increaser necessary to make adjustments 3. With spa circulating pump on high speed, add required amount directly into spa water 4. Continue circulating water a minimum 20 minutes 5. Do not pre-dissolve this treatment as heat is generated when it contacts water 6. Retest and adjust if necessary