DISINFECT THE WATER, SANITISER (chlorine)

Swimming pool/spa water is re-circulated and constantly re-used, and some of the bacteria, viruses and other micro-organisms deposited by bathers must be destroyed before they can pass from one bather to another. So the water must be disinfected using a sanitiser

REMOVE IMPURITIES - SUPERCHLORINATE (granular shock chlorine)

The impurities introduced by bathers need to be removed and by-products from these reactions need to be broken down to achieve good water quality and bather comfort. So the pool should be treated with a shock treatment.

PH LEVELS, WATER BALANCE (PH-Plus & PH-Minus)

Water must be kept in balance (neither too acidic, nor too alkaline) to ensure the pool, equipment and fittings come to no long-term harm through corrosion or scale formation. The sanitiser you use will aslo be more effective if the water is balanced.