Balancing Your Pool Water – Total Alkalinity
Understanding Total Alkalinity (TA)
Total alkalinity (TA) is a measure of the ability of water to resist changes in pH and acts as a buffer in controlling pH change. TA is an important factor that should be taken into account in optimizing water conditions. Testing and correcting TA should be done before testing and adjusting pH. The ideal range for TA in pools using Pulsar® calcium hypochlorite sanitizer, is 60-180 ppm*.
If the TA is below 60 ppm, the pH will not stay in the proper range and the pool water may promote corrosion and cause damage to pool fixtures and equipment. TA that is above 180 ppm can cause cloudy water or scale. NOTE: Cyanuric acid (a stabilizer) will interfere with the test for total alkalinity. Therefore, it is necessary to compensate for this interference.
For pools with properly maintained pH and a cyanuric acid level above 30 ppm, the correction formula is:
Tested Total Alkalinity Result – 1/3 Cyanuric Acid Reading = TRUE TOTAL ALKALINITY.
In other words, subtract one-third of the cyanuric acid reading from the tested total alkalinity reading to compensate for the interference.
*MAHC 188.8.131.52.1A Total Alkalinity Levels Total alkalinity shall be maintained in the range of 60 to 180 ppm (mg/L).