Why do I need chlorine?

While a filtration system will remove solid matter from your pool, no amount of filtering will remove bacteria.  The addition of a sterilizer (chlorine) is therefore a must to keep the pool in a healthy and clean condition.  The chlorine has one fault, however, and that is the available chlorine is easily dissipated by sunlight.

The answer is to chlorinate the pool after sunset or as close as possible to stop waste and prevent a build-up of bacteria.  As stated, sunlight will dissipate chlorine and so a reading of the chlorine level with the test kit supplied can only be done first thing in the morning for a true reading.  The dissipation is overcome by the addition of a chlorine stabiliser.

The stabiliser used is called cyanuric acid and acts as an ultraviolet screen.  It can be added to the pool either in a concentrated form or as a chlorinated cyanurate compound (stabilised chlorine).  It is advised that a cyanuric test kit is used to maintain the correct level.  A free chlorine residual of 1.5 - 2 ppm is essential to ensure safe, healthy water and a stabilised chlorine system.