ProTeam Calcium Up is an easy and effective way for pool owners to boost their calcium hardness into the optimal 150-350 ppm range, preventing corrosion damage to plumbing, equipment, and surfaces. Its fast-dissolving granules quickly get to work boosting calcium hardness, which makes water balancing much easier and hassle-free as well as improving the effectiveness of any pool chemicals. Best of all, water quality will be much improved with virtually no eye or skin irritation to bathers, letting them spend hours enjoying the pool. Calcium Up is made in the USA to ensure quality, allowing you to buy with confidence.