Balancing pH and Total Alkalinity

Owning a swimming pool can be a lot of fun especially when you can jump into a beautiful blue, clean, warm, and clear water! The key factor in this though is making sure your water chemistry is properly balanced. Most swimming pool owners know about chlorine, Calcium Hardness, Cyanuric Acid (CYA) but today we want to focus on pH and Total Alkalinity (TA). These two values are vital to your water chemistry and making sure your water remains blue and clear. These two key components are often left out and misunderstood in regard to their importance and we want to make sure you understand why they are key factors in keeping your pool clean and ready to swim in.


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 be basic or what is defined as “alkaline”. To have pH in balance we must adjust the water with additions of acid (pH decreaser) or bases (pH increasers)  to help you obtain an optimal range of 7.4 – 7.8 which is the standard optimal level in the swimming pool industry. If your testing shows a pH value below 7.0; the water is in a corrosive (acidic) condition and you will need to add a base to bring the pH up. Please note, a low pH will weaken vinyl, strip heat exchangers and erode the interior finish of your swimming pool. Whereas, if the pH is above 7.8, the water is considered basic and you must add acid to bring down the pH to prevent the formation of scale or calcium deposits on your water tile line, the filtration equipment, and the possibility of having cloudy water. Another issue with a high pH is chlorine becomes less effective. This is the most common of the two!

Total Alkalinity

Total 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 bicarbonate alkalinity, which should be between 80 parts per million (ppm) and 120 ppm. When the TA is within this range, it prevents rapid pH changes and ultimately stabilizes the pH level. TA is extremely important and often forgot about when it comes to water chemistry.

When you want to achieve a swimming pool with balanced water chemistry, adjusting your pH levels is critical. Please note if you own a salt chlorinator it will cause your pH to increase more rapidly. This should be monitored regularly to prevent scaling. If you should have any questions about pH or TA, please don’t hesitate to contact us today!