Thursday, September 17, 2015

Total Alkalinity (TA) is a measure of water's resistance to change in pH:

In basic terms TA acts like a buffer for your pH level. Picture 2 people of equal weight on a playground see-saw. Imagine the seesaw is a pH indicator, and the 2 people are each a representatives of the "Acid" family and "Base" base family. In this image, the seesaw balances, which relates to pH neutral but the total alkalinity is low because there is only one member of each family on the seesaw. If one of these people were to suddenly jump off the seesaw, there would be a drastic swing in the pH level and the other side of the seesaw would crash to the ground.

Now picture the same seesaw with 10 equally weighted people on either side, the pH is again balanced but now the total alkalinity is high enough so that if one person were to get off of the seesaw the balance would not change as drastically due to the 9 remaining people acting as a counterbalance.

There are a number of products available such as T.A Plus that you can use to increase the pools Total Alkalinity - check the instructions for dosing details.

When your swimming pool TA is kept sufficiently high you not only stabilize pH levels, but you optimize sanitizer efficiency, and help prevent corrosion.

Care must also be taken so that your total alkalinity doesn't go above recommended levels. Signs that your total alkalinity is to high include scaling and clouding of hard water. Pool suppliers' recommendations concerning total alkalinity vary widely, but most of these recommendations fall within the range of 80-150 ppm (parts per million) of alkalinity. The higher ranges are recommended when the pool water pH will tend to drift down, as in rainy seasons, and when acidic sanitizers are used.

Research studies have shown that there is a clear relationship between pool pH and total alkalinity present in water. In general, when alkalinity increases, the pH of the pool tends to be higher. More specifically, when alkalinity is adjusted to the range of 80 to 150 ppm, it maximizes the likelihood that the pool pH will hold in the range of 7.2 to 7.8.

If the TA is too low:

• pH will be unstable and difficult to maintain.
• pH changes rapidly when chemicals or impurities enter the water.
• pH may drop rapidly causing etching & corrosion.

If the TA is too high:

• The pH will be difficult to adjust.
  
• A High pH level often occurs.
• This causes cloudy water, decreased disinfectant effectiveness, scale formation & filter problems.

Learn More About pH