Maintaining proper water chemistry in your swimming pool is key. It is often thought proper water maintenance only involves adding chlorine and adjusting the pH. In reality, swimming pool maintenance is much more than that.

Their are several factors that affect water quality. These are listed below along with their ideal levels.

pH- ph refers to the degree of activity of an acid or base in the water. pH is the most important factor in swimming pool water chemistry. pH is measured on a scale from 0 to 14 with 7 being neutral. Below 7 is considered acidic while above 7 is considered basic. APSP guidelines state that the pH of a swimming pool should fall between 7.2 to 7.8. If the water is below 7.2 it is considered to be corrosive and chlorine becomes unstable. The lower pH causes the chlorine to become more efficient but the unstabliity results in the consumption of larger quatities. High pH can form scale or cloudy water and chlorine becomes less effective but more stable.

TA- Total Alkalinity refers to the ability of the pool water to resist an unexpected change in pH. It does this by acting as a buffer so that when materials are added to a pool that would cause the pH to go up or down, these changes are controlled and do not result in severe changes to pool water balance. TA is best kept in the range of 80-120ppm. If TA is below 80ppm the water can become corrosive and the pH can swing easily upward and downward and back again. Above 120ppm and the water can become cloudy or form scale and the pH will slowly rise.

Calcium Hardness- The sum of all calcium dissolved in water is referred to as Calcuim Hardness. Calcium should be maintained in the range of 100-400ppm. Like pH and TA high levels of calcium (hard water) can cause cloudy water and scale formation. Low calcium (soft water) can be corrosive actually dissolving the calcuim in plaster.

Chlorine- Chlorine is the most commonly used sanitizer and is broken down into three categories- Free Chlorine, Combined Chlorine, and Total Chlorine. Free Chlorine is the most desirable because it responsible for the actual disinfection. Once Free Chlorine has reacted with bacteria or bather waste it changes and is referred to as Combined Chlorine. Total Chlorine is the sum of both Free and Combined Chlorine. Free Chlorine should be kept at about 10% of the current Cyanuric Acid level in the pool. Cyanuric Acid will be discussed on the following page.

More Factors and Chemistry Adjustment