Owning a swimming pool can be a lot of funespecially when you can jump into beautiful blue and clear water! The keyfactor in this though is making sure you have a balanced water chemistry. Inthe past, we’ve talked about chlorine, Calcium Hardness, Cyanuric Acid (CYA)but today we want to focus on pH and Total Alkalinity (TA). These two valuesare vital to your water chemistry and making sure your water remains blue andclear. They are also often misunderstood in regard to their important and wewant to make sure you understand why they are key factors in keeping your poollooking great!
pH is a measure of how acidic or basic the pool water is. pH is measured on a scale from 0-14, with 7.0 being neutral. Below 7.0 is defined as being acidic, while levels above 7.0 are said to bebasic or alkaline. To have pH in balance we must adjust the water withadditions of pH decreasers (acid) or pH increases (bases) to help youobtain an optimal range of 7.4 – 7.8 which is standard optimal level in theswimming pool industry. If your testing shows a pH value below 7.0; the wateris in a corrosive (acidic) condition and you will need to add a base to bringthe pH up. (This is only common if you add too much acid to your pool) Pleasenote, a low pH will weaken vinyl, strip heat exchangers and erode theinterior finish. Whereas, if the pH is above 7.8, the water is considered basicand you must add acid to bring down the pH to prevent the formationof scale or calcium deposits on your tile, the filter, and the possibilityof cloudy water. Another issue with a high pH is chlorine becomes lesseffective. This is much more common of the two!
Alkalinity is a pH buffer, meaning it helps to keep the pH from drastically moving up and down the pH scale by absorbing major changes to the waters before affecting the pH. Total Alkalinity (TA) is a close relative to pH and is a measure of how much of the alkaline substances that are in the water. In the swimming pool water, we are concerned with bicarbonatealkalinity, which should be between 80 parts per million (ppm) and120ppm. When the TA is within this range, it prevents rapid pH changes andultimately stabilizes the pH level.
When you want to achieve a swimming pool with
balanced water chemistry, adjusting your pH levels is critical. Please note if
your salt levels are high that will cause your pH to increase more rapidly. If
you should have any questions about pH or TA, please don’t hesitate to contact