Chemical treatment, cleaning

Press, 26 November 1980, Page 20

Chemical treatment, cleaning

For summer maintenance about half a day per week is all that is needed and in winter

maintenance is negligible if the pool is covered. In summer the filter should be running at least three hours a day or more depending on use of the pool. As a guide, the bottom should always be clefirly visible at the deepest point. Apart from regulation of the filter, the other frequent chore is chemical treatment. With a test kit, this is a simple operation. It involves filling a small container with a sample of pool water from below the surface and adding a few drops of the test solution supplied.

This “doctored” water is then compared with colour standards in the kit to determine the acid/alkali balance in the pool water. In alkaline water, disinfectants are less effective against bacteria and algae, whereas acid water irritates eyes and skin. As

over acidity is more serious, the pool water is better to be slightly alkaline — which means keeping the pH value at about 7.2.

This test should be done twice weekly during the summer, but once a week or less should be enough in winter.

Commercial additives are available under various brand names to correct any imbalance in pH. Along with this, there is a similar test done to check the amount of disinfectant residual present, as regular dosing is needed .with a chlorine or similar compound to kill bacteria and control algae. A third simple water test that is useful is one to measure the quantity of carbonates present. This is referred to as the “total alkalinity.” . If it is kept in the range of 50 to 100 parts

per million, the pH fluctuation is minimised, hard water scaling is reduced and corrosion of metal equipment and cement is prevented. The other regular maintenance chores are the routine cleaning procedures.

It makes sense to use the leaf skimmer often, as it is much easier to skim the surface than dredge the bottom. Even so, vacuuming should be done at least once a week. To be kind to the equipment, back-washing of the filter is best done at regular intervals and the skimmer and pump strainers kept Clear of rubbish. The scum that forms on the waterline tile is a combination of oil and dust that can usually be removed with a rag and ordinary cleaning powders,