Understanding pool water chemistry is the single most important skill a pool owner can develop. Properly balanced water keeps swimmers safe, protects your pool equipment from corrosion, and prevents unsightly algae growth. While it might seem complex at first, mastering the basics of pH, chlorine, and alkalinity is easier than you think.
pH measures how acidic or basic your water is on a scale of 0 to 14. For swimming pools, the ideal range is 7.2 to 7.6. Water that's too acidic (low pH) can corrode metal equipment, etch plaster surfaces, and irritate swimmers' eyes and skin. Water that's too basic (high pH) reduces chlorine effectiveness and can cause cloudy water and scale buildup. Use pH increaser (sodium carbonate) or pH decreaser (sodium bisulfate) to make adjustments.
Total alkalinity acts as a buffer for pH, preventing it from swinging wildly with every addition of chemicals or rainfall. The ideal range is 80 to 120 parts per million (ppm). When alkalinity is in range, pH stays stable and is much easier to manage. If alkalinity is low, add sodium bicarbonate (baking soda). If it's high, you can use muriatic acid to bring it down — but do this carefully, as it also affects pH.
Free chlorine is your pool's primary sanitizer, killing bacteria, viruses, and algae. Maintain levels between 1 and 3 ppm for daily swimming. Chlorine comes in several forms: liquid (sodium hypochlorite), granular (calcium hypochlorite or dichlor), and tablets (trichlor). Each has pros and cons. Tablets in a floating dispenser or inline chlorinator provide steady, low-maintenance dosing, while shock treatments (super-chlorination) are used weekly or after heavy use to oxidize contaminants.
Test your water at least twice a week during swimming season using test strips or a liquid test kit. Record your results to spot trends early. Remember that factors like rain, heavy bather loads, and high temperatures all affect chemistry. If you're ever unsure about your water balance, bring a sample to a pool professional or contact DR Installs for expert water testing and treatment services.
Need help with your pool?
Schedule a service with DR Installs today! Our experienced team handles everything from pool openings and closings to equipment repairs and full installations.
Schedule Service (815) 483-9713