Why Use Alkalinity?

The total alkalinity (TA) is a measure of how much of the alkaline substances there are in the water. In the swimming pool water, we are concerned with bicarbonate alkalinity, which should be between 80 ppm and 120 ppm.

When the total alkalinity (TA) is within this range, it prevents rapid pH changes and “stabilises” the pH level.

If the TA is too low, Marbelite and plaster walls will become etched, metals corrode, the pool’s walls and floor can stain, the water can turn green, eyes burn and we can have pH bounce (pH rapidly going up and down, seemingly at random).

If the TA is too high, the pH is difficult to adjust, the water becomes cloudy, the pool constantly needs acid (according to your test kit) and the chlorine loses its efficiency as a disinfectant.

It is recommended that you test the TA regularly, but in practice it changes very little in a well-maintained pool.

To raise the level of TA, you should use our Hot Tub and Swim Spa Company Alkalinity Increaser. To increase your TA of 10ppm, use 1,5kg per 100m3. Raise alkalinity gradually continuing treatment daily until correct levels are reached.

Lowering the total alkalinity is also a slow process. To reduce pH readings add 10g per 1000lts of Spa pH and Alkalinity reducer, sprinkling product directly to the water with circulation on. This application will lower the pH by approximately 0.2.Only make one addition of pH and Alkalinity Reducer at a time and always re-test the water, should a further addition be required, test your water again.To reduce Total Alkalinity add 15g per 1000lts of Spa and Hot Tub water with circulation on. Add product to the deepest point of the Spa / Hot Tub in one application. This application will lower the Total Alkalinity by approximately 10 – 20 ppm (mg/l). Always re-test the water after each application.