Alkalinity Testing - Testing Your Total Alkalinity Regularly is Required

Total alkalinity testing of your swimming pool or spa, should be done several times a week! This is the norm so as to ensure that it is within recommended industry standards. Although alkalinity affects the water balance of your swimming pool or spa, it also effects all your other pool water parameters as well.

This statement applies especially to your pH levels of these water facilities.

The total alkalinity, in case you didn't know, is considered the governor of pH. It is so - because it is the buffering system for your pool water.

If at any time your total alkalinity is too low, you will experience what we in the pool industry call pH bounce with your pool.

Testing the total alkalinity for your swimming pool or spa

The test for the total alkalinity of your pool or spa is a titration type test that usually employs three different types of reagents. These reagents include:

  • A chlorine neutralizer. This reagent is the first of the three to be used. When beginning your testing, you will add about two drops of this reagent to your water sample.

    This reagent is utilized in your testing because it removes any chlorine content from your sample, that could interfere with the second reagent and give you a false reading.

    If you have a portable Taylor test kit, this reagent will be the one marked R-0007. If your water sample contain a chlorine level that is above 5.0, just simply add more of the reagent until your is completely neutralized of its chlorine content.

  • A total alkalinity test solution. This is the second reagent to be added next. It is also referred to as a color indicator. This indicator turns green if an alkalinity level is present in your water sample. Again if you are using a Taylor test kit, this reagent will be marked R-0008.

    When conducting your TA test, you will add 5 drops of this test solution to your water sample, give it a little swirl, and take your reading.

  • A calibrated solution of sulfuric acid (the titrant). This solution is added drop by drop until the green color turns sharply to a red coloration. While adding the drops to your water sample, you will count the amount of drops until your sample changes color.

    Once you have the count of the amount of drops it took to change the color of your water sample, you would then multiply by ten (eg. 8 drops multiply by 10 equals 80 ppm). This is would be your actual TA level in your swimming pool. This means that each drop of the titrant test solution during your alkalinity test, equals 10 ppm of TA.

    At this particular stage of your total alkalinity test, you are observing your pool water's resistance to the pH change. We call this part of your test, titrating your water sample. This TA test reagent is marked R-0009 in your Taylor test kit.

Factors that can interfere with your total alkalinity testing results

As I mentioned earlier, you have to follow a sequence of events in order for you to get your desired TA readings. One problem that usually occur is that you may experience a blue to yellow color change in your water sample instead of it going from green to red.

This is usually an indication that your chlorine levels are extremely high in your pool. For you to get the correct reading for your total alkalinity, you have to neutralize all chlorine content form the water sample. And to achieve this, like I mentioned before, you simply add a few more drops of your R-0007 chlorine neutralizer.

Oxford Above Ground Swimming Pool Kit - 12'x18' Oval

Misconception when testing total alkalinity in swimming pools

There are some individuals that believe that we should subtract one third of our stabilizer (cyanuric acid) from the final results of our total alkalinity test. According to these folks, this equation would give us our true alkalinity results. Listen nothing could be further from the truth.

The stabilizer in your pool is cyanuric acid and it does not show any reaction to the chlorines that we use in the industry today.

Your stabilizer will not be registered as a carbonate alkalinity. Your alkalinity is equal to the stoichiometric sum of the bases in solution.

Carbonate alkalinity tends to make up most of your total alkalinity in a natural environment. This my friend, is due to the natural events and dissolution of carbonate rocks and the presence of carbon dioxide in our atmosphere.

Common natural components that can contribute to your total alkalinity.

These components include:

  • Borate.
  • Hydroxide.
  • Phosphate.
  • Silicate.
  • Nitrate.
  • Dissolved ammonia.
  • The conjugate bases of some organic acids and sulfide.

If you noticed, I did not mentioned anything about cyanuric acid as a contributor. Therefore it will not affect the accuracy of your total alkalinity test at all.

Understanding your alkalinity test results

The table below will give you a clear indication of your alkalinity test results.

Corrosive EnvironmentWater BalanceCloudy Water
When TA is too low: 50ppm - 80ppmWhen TA is just right: 80ppm - 110ppmWhen TA is too high: 110ppm - 140ppm.

As pool and spa owners/operators, we need to maintain our TA levels between 80 and 120 parts per million. At this range, we will provide an optimal buffering environment (alkaline materials in solution) that is necessary, to control any pH swings in our pool water.

Problems related to improper total alkalinity readings

When you ignore or don't conduct regular total alkalinity testing, you will experience some serious problems in your recreational water facility. For instance, if your total alkalinity readings are too low, you will have pH bounces.

This is when your pH swings up and down widely. This particular problem causes damage to your swimming pool and to your mechanical systems.

If your TA is too high, the results can and usually is cloudy water in your pools and spas. This normally is a clear indication that your pool water is over saturated and needs to be corrected. So, always try to maintain a proper TA level so that you control any possible pH swings.

Hence you will safeguard your pool plaster from any attacks due to pH bounce because you are conducting regular total alkalinity testing.

Alkalinity testing must be done regularly to determine your total alkalinity level.

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