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How to Add Chlorine to a Pool

By Melissa Lewis ; Updated September 21, 2017
Add Chlorine to a Pool

When chlorine is placed in water, it has a sanitizing effect and is therefore used in pools where water is not drained or dumped after each use. It is, however, a dangerous chemical where the right dosage is of the utmost importance. If there is too much chlorine in a pool, it could cause a swimmer's skin to become irritated and eyes to become red. Rarely, it could produce a gas in which breathing may become difficult. If there is not enough chlorine, microorganisms could thrive and your pool will no longer be a sanitary place to swim. For these reasons, it is important you follow proper procedures when purchasing and adding chlorine to your pool.

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.



  • Add chlorine to your pool in the evening so that you can test the levels later in the evening or in the morning before anyone uses the pool.


  • Always read manufacturer directions and consult a pool specialist about all products used. Always test your chlorine and pH levels before letting anyone swim.

About the Author


Melissa Lewis is a former elementary classroom teacher and media specialist. She has also written for various online publications. Lewis holds a Bachelor of Arts in psychology from the University of Maryland Baltimore County.