What is Total Alkalinity, what is the acceptable range, and how often should I test it?


Total Alkalinity is a measurement of how alkaline the water is (how many alkaline substances are in your pool water). The total alkalinity should be maintained in the range of 80ppm – 120ppm, this is considered to be the “ideal” range. Maintaining this ideal range is important for keeping the PH from fluctuating rapidly up and down on the PH scale. With the total alkalinity in the ideal range it “stabilizes” the PH and prevents this rapid fluctuation. This is a critical part of keeping your water clean because the total alkalinity effects the PH and in return the PH ultimately dictates how effective all of your products will be in the water. There are also some other adverse effects from the total alkalinity not being maintained within the ideal range. If the total alkalinity is high your pool water can become cloudy, the chlorine will become inefficient, and adjusting the PH will be problematic (you will constantly have to add acid to lower the PH). On the other hand if the total alkalinity is low metal fixtures will start to corrode, staining of the pool surface can occur, plaster pools can become etched, can cause burning or irritated eyes, and the water can turn green. Total alkalinity should be the first thing checked and balanced and should be tested at least every two weeks to assure proper water chemistry.