Of the pool and spa filtration media on the market, sand is the least effective among the three commonly used filter types (the others being DE and Cartridge) in terms of particle size removed.
While cartridge filters can remove particles of about 8 to 10 microns, and DE removes particles as small as 1 micron, sand removes particles of about 30 microns, allowing smaller particles to pass through and compared to the others, produces the lowest water clarity.
That said, sand filters are the least expensive of the three and offer the advantage of easy cleaning – simple backwashing.
But for those who want superior water clarity, it has long been understood that sand filters are not the best option.
These days, there are several new options to replace sand filter media, touted by manufacturers to dramatically improve a sand filter’s performance and in some cases, reduce maintenance.