How to Add & Test Pool Chemicals

Testing and balancing your above ground pool’s water chemistry is not rocket science – it’s chemistry!

Luckily, for those of us who with lacking science skills, pool chemistry with a few basic supplies.

Regular testing and balancing your pool’s chemicals will not only prevent algae and bacteria growth, but, along with regular cleaning, it’ll also lengthen the life of your pool liner. And it’ll keep your above ground pool safe for swimming.

Properly testing your water will save you money too. You’ll know when you chemical levels are good, and you’ll avoid wasting anything.

Use this quick guide to pool chemicals to get started!

How to Test the Water in an Above Ground Pool

Before you test and balance your pool’s water chemistry, you should follow these general tips:

  • Make sure your pump is running so that the chemicals can circulate through the entire system.
  • Determine the size of your pool and the chemical limits on the chemicals you need to add. If you need to add more than the max limit, you’ll need to wait to do so.
  • Test your pool in the morning to get the most accurate reading of free and available chlorine.
  • Check the expiration date of your test kit or test strips. An old kit can give faulty readings.
  • Wait at least 24 hours after adding chemicals to test again and add any more.
  • Take a water sample from about 1′ below the surface.
  • Clean the pool before testing and adding chemicals.

Try to find a test kit that can test free available chlorine, cyanuric acid, pH, alkalinity, and calcium hardness.

Above Ground Pool Chemical Tests

To test and balance the water in your above ground pool:

  • Take a water sample from about a foot below the surface. Elbow deep is a good reference point.
  • Check the alkalinity first.
    • Range: 80 to 140 ppm.
    • If alkalinity is too low, add an Alkalinity increaser.
    • If alkalinity is too high, add an Alkalinity decreaser.
  • Check the pH levels.
    • Range: 7.2 to 7.6.
    • If pH is too low, add a pH increaser.
    • If pH is too high, add a pH decreaser.
  • Check the water hardness.
    • Range: 200 to 400 ppm.
    • If water hardness is too low, use Calcium Chloride to raise it.
    • If water hardness is too high, you may need to drain or partially drain the pool and add new water.
  • Check the cyanuric acid (conditioner/stabilizer).
    • Range: 50 to 70 ppm.
    • Add if necessary.
  • Check the chlorine.
    • Range: 1 to 3 ppm.
    • Add if necessary.
  • If you needed to add any chemicals, allow the pump to run for about 24 hours before testing again.

Supplies Needed to Test and Balance Chemicals

To test and balance the chemicals in your above ground pool, you’ll need:

  • A Pool test kit. (Either paper strips or liquid).
  • Chlorine. (liquid or tablets)
  • Alkaline balancer.
  • pH balancer.
  • Water calcium hardness balancer.
  • Water stabilizer/conditioner. (Cyanuric acid).

It’s helpful to keep a log of your water chemical tests to not only keep track of what’s changing and protect against false readings, but to help remind yourself to do it.

Remember to always store your pool chemicals in a secure, dry, cool place. Be sure all containers are properly sealed and well out of the reach of children. Pool chemicals can be dangerous is used improperly or if you get them on your skin/eyes or ingest them. If you do not feel comfortable handling pool chemicals, consult a professional.

Water Testing Tips

To get the most accurate test results to ensure you’re adding chemicals properly, be sure to follow the test kit or strip instructions. In general:

  • Use fresh test reagents and strips.
  • Store your test kit in a cool, dry, and dark place.
  • Close your kit and containers tightly.
  • If readings are really off from previous tests (refer to your log), retest again before adding any chemicals.
  • Both paper strips and liquid reagent test require a few moments to react. Wait until the color changes to record your results, but don’t wait too long or you’ll have a false reading.

And that’s all there is to it! If you’re new to testing pools, you may need to refer to these directions or the directions on your test kit the first few times you do it, but after just a little bit, testing your water will become second nature.

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