Water Balancing

Controlling the pH of your pool

The degree of acidity or alkalinity of water is measured by it's pH value. A pH of 7 is neutral; a fall below 7 indicates increasing acidity, and a rising above 7 indicates an increasing degree of alkalinity.

For healthy pool water a pH value of around 7.2 - 7.6 should be maintained. The pH of the water should be measured regularly and adjusted accordingly.

Alkaline Conditions - pH greater than 7

A pH of above 7 indicates the presence of alkaline substances.

If the pH value rises above 8 the effectiveness of the disinfection process is reduced and the water has an increasing tendancy to precipitate hard salts. The water can become cloudy and the filter capability reduced, due to blockage.

Acidic Condition - pH lower than 7

A pH value below 7 indicates the presence of acidic substances.

If the pH falls, the water becomes increasingly corrosive to metals and the chlorine level decreases, weakening the disinfection process.

Finally, and most importantly, if the pH is too low or high, irritation to the eyes and skin may be caused by the water.

Ideal pH

A pH value in the range of 7.2 - 7.6 is the ideal range for healthy pool water.

In practice, it is sufficient to keep the pH value within an optimum range for each disinfection.

pH Adjustments

The chemicals needed to adjust the pH depends on the disinfection being used.

Chlorinated Isocyanurates and chlorine gas (which produce acidic reaction products) are acidic and require the addition of alkali, usually Sodium Carbonate.

Calcium or Sodium Hypochlorite are alkali and require the addition of an acid, normally Sodium Bisulphate.

pH Testing

A simple to use kit is available to test the pH of your pool water from Mister Sparkle Swimming Pools range of chemicals.