General Water Testing Tips


Testing your pool water is easily one of the most important things you can do for your pool. By obtaining an accurate reading of your water chemistry, you can understand exactly how much product to put in your pool. This not only saves you money by preventing the possibility of over-treating your water, but also keeps your pool healthy all year long.

While testing your water can be completed at a local Leslie’s store, there are also home options available for you to use such as test kitstest strips, and electronic testing equipment.

While testing your water at home is simple, there are a few things you should know to ensure proper readings.

  • When taking water samples, the ideal sample will be from about 12”-18” below the water surface after the system has been on for around an hour.
  • High chlorine levels can skew other readings such as pH and total alkalinity. If high levels of chlorine are present, make sure to use a chlorine neutralizer per the instructions on your kit.

Note: There is no chlorine neutralizer for test strips. Therefore, a test kit using reagents may be a better option if you experience high chlorine levels regularly.

  • If you are having chlorine issues in your pool, the best time to get a water sample is in the morning. Even with proper amounts of chlorine stabilizer in the pool, chlorine will be burned off during the day. By testing it in the morning, your pool water has had a chance to circulate all night and your levels are only minimally influenced by the sun.
  • When using test strips, there is usually a 10-20 second wait period for the pool water to change the colors on the strips. Once the stated time period has passed, compare the test strip as soon as possible. Waiting too long may allow the colors to continue changing, in turn giving you an inaccurate reading. This applies when using reagents as well.
  • When using a test kit, slowly add the reagents to the water. Sometimes, reactions in the water take a moment to occur. Adding reagents too quickly may skew your readings.
  • Store all test materials in a cool, dark area.
  • Check your testing materials for accuracy on a yearly basis. Like most things, these materials can expire. When that happens, readings are typically incorrect.
  • Even if you test your water at home on a consistent basis, taking a sample into a local Leslie’s store to get complete test results ensures all aspects of your water are in their proper ranges.
  • Water tests should be completed before adding any chemicals. On that same note, pool chemicals can take up to a day (sometimes longer depending on the product) to have their full effect seen in a water test. Therefore, it is a good rule of thumb to wait at least 24 hours after adding chemicals to test your water again.
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  • If you have any other questions about water testing, please call us at 1-800-LESLIES or visit your local Leslie’s store.
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