HAYWARD TOP CLOSURES DOME FOR SAND FILTERS #SX244K

HIGH RATE PROSERIES

The oldest and most popular method of filtration is sand. Sand filters share two things in common: They all have some sort of lateral or under drain with slots to hold back sand while allowing clean, filtered water to pass through. High-rate sand filters use a special filter sand, normally .45 to .55mm (also known as pool-grade #20 silica sand), it has sharp edges that serve to separate particles, allowing filtration to take place. They operate on the basis of 'depth' filtration; dirt is driven through the sand bed and trapped in the minute spaces between the particle of sand. Initially, a clean sand bed will remove larger particles, and then, as the bed starts to load up, it will remove finer particles.