Pool filters and their correct use are vital to the smooth operation of a swimming pool. In fact, filtration is probably the most important part of pool water treatment.

Insoluble water pollutants, from dust and vegetation to skin flakes and hair, provide nutrients for algae and bacteria unless they are removed by filtration. No sanitiser can deal with that kind of pollution. An efficient filter is as essential as a good sanitiser.

There are three types of filters commonly used:

Sand Filters

These are efficient, need little maintenance and are the most commonly used filters in New Zealand. The pool water is either pushed or sucked through a bed of sand, and dirt particles are entrapped on the way.

To clean the filter, the water flow is reversed so that the dirt is dislodged and flushed to a waste pipe. This is referred to as backwashing to waste. Sand filters are used with belowground pools and larger volume aboveground pools.

Cartridge Filters

Cartridges are made up of supported fluted paper, cloth or polypropylene which does the filtering. They are inexpensive, but the least efficient of the three types. They can be cleaned using Bluewater Filter Cleaner or by being left to dry so that the dry material can be brushed off.

Diatomaceous Earth Filters

These may be used with above or belowground pools. Cloth, supported on a plastic frame, is coated with diatomaceous earth. It is this which does the filtering. These filters are capable of removing finer particles than a sand filter, but they require frequent manual cleaning and recharging with RS400-20 product.

Backwashing can be done by removing the supports, hosing down and recharging with diatomaceous earth is recommended. Every third or fourth clean should involve soaking the supports in Bluewater Filter Clean before hosing.

Cleaning Devices

There are numerous cleaning devices available. Vacuums running from the pump suction or pressure lines enable leaves, grass clipping, dust and other debris to be removed from the pool floor and walls.

Manual cleaning implements such as vacuum head, brushes and leaf scoops are also useful.