Purchase the chlorine product best-suited for your pool. There are many types of chlorine products. Liquid chlorine is used for larger commercial pools and is very difficult to use for the average pool owner. There are also tablets that contain chlorine and a chlorine stabilizer or conditioner. You can also purchase granular chlorine that dissolves quickly. It is best, however, to talk to a pool specialist about your pool, its size, and filter and pump system.
Use the correct amount of chlorine. After you purchase your chlorine, you will need to carefully put the chlorine in the correct location in the pool, either in the floaters, skimmers or in-line erosion feeders. As a general guide, for every 1,000 gallons of water, you will use ½ oz. of Calcium Hypochlorite Granulars, three Calcium Hypochlorite Tablets, or 1.5 oz. of Sodium Hypochlorite 15% Solution. However, it is essential that you follow the manufacturer's directions and wear gloves and goggles as a precautionary measure.
Add chlorine stabilizer. You may need to add a chlorine stabilizer or conditioner to your pool, as well. Discuss this with your pool specialist, but depending on the chlorine you use, you may only need to do this once per season or once every few weeks.
Test your chlorine levels a couple of hours after adding more chlorine. Also test your pH levels since they are often affected after adding chlorine. Do this before you let anyone swim. If necessary, add the correct chemicals to bring your levels back to normal. Follow all manufacturer directions and test again before allowing swimmers in the pool.