For an optimal water treatment in the private swimming pool is the weekly Backwashing of the filter circuit of particular importance. Constant to ensure optimum water quality in private swimming pool, work on the sand filter system must be carried out regularly. Furthermore, are to check the water values of pH and chlorine content and adjust if necessary. But first to work on the equipment: the filters, which usually from PP or Fiberglass is manufactured, is an equivalent amount of quartz sand grain size from 0.4 to 1.0 mm filled. This quartz sand has the function to absorb the solids in the swimming pool water or contaminating substances. This is hair, dandruff, insects, leaves, flowers, etc.

The swimming pool water is sucked in via the filter pump swimming pool and pressed with a carefully calculated speed through the sand bed in the filter tank. The water flows through the small openings between the sand grains again to the bottom of the filter and is there on special cartridges the pool returned to. The pollutants that are larger than the openings between the grains of sand, can freely pass through the filter sand and become lodged in the sand. Where is the speed of pressing water through filter sand of particular importance. Should be neither too high nor too low. The filter speed is too high, creates a resistance in the filter which makes for an extremely high pressure and eventually can lead to mechanical damage to the boiler. Filter for low-speed, is no sufficient circulation of swimming pool water.

The tanks, filter pump performance and filter surface are in a close relationship and a filter velocity of 30 m / h is called optimal. The constant increase in pollution in the swimming pool (especially in outdoor pools) rises also the dirt in the filter tank. This automatically leads to a pressure build-up in the tank.