The process of UV (Ultra Violet) light treatment requires water to pass across a UV lamp. The UV light destroys bacteria and other pathogens in the water in order to make it safe for potable use. This process requires the water to be completely free of particles. Any particles in the water can cast a shadow in which bacteria can still survive, so a very fine pre UV filter is required.
Removing the particles prior to UV treatment is fundamental for the process to work. The water must be filtered to 5 microns before it is ready to go through the UV filter. There are a number of different pre UV filter units available, and these can be single, dual or triple stage.
The Hydra Rainmaster pre UV filter unit shown has the benefit of a back-washing valve on the first stage that is used to reject the accumulated debris. This can be manually operated, or automated by combining with a solenoid valve and timed power supply.