Diatomaceous Earth (D.E.) filters are the best quality pool filter available. Used by Coca Cola in the production of soft drink they filter down to 5 microns. D.E. filters consist of a number of material elements inside a large filter. These elements are coated in Diatomaceous Earth and it is this combination that produces their excellent filtration quality. One problem with D.E. filters however is their cost. Ongoing maintenance requires a continual supply of diatomaceous earth and parts, such as the elements can be worth up to $100 each making them expensive to repair. They are also expensive to purchase initially and can cost up to twice that of a sand filter. In most cases a cartridge filter is a simpler replacement for an ageing D.E. filter.
Due to their cost, the level of maintenance required and the use of diatomaceous earth, which the water board is trying to stop being put down drains, they are slowly disappearing from the market. This is also making their cost increase. A larger cartridge filter or a sand filter and the occasional use of pool blue cubes or filter alum will require considerably lower maintenance and years of reliable operation.
As time constraints increase most people opt towards sand filters due to their minimal maintenance requirements. Most sand filters come with a 10 year tank warranty ensuring years of reliable operation.