For years, sand filtration has been the norm for most pool filtrations. Until recently, sand was the only media used besides DE. Sand filters by physical entrapment. The sediments and particulates were caught on the top of the sand and when the filter became dirty, it would be backwashed. Sand has it’s limitations as it will only filter down to 100 microns, so a lot of particulates would pass on through leaving a cloudy look from Total Disolved Solids (TDS) in the pool water. Sand also breaks down over time, and becomes channeled, allowing water to pass through the filter
un-filtrated. Pool companies came out with special chemicals to use to help clarify the water and to loosen the sand. Instead of trying to improve on the filtration, they resorted to more chemicals,
leaving you to swim in a sea of chemicals.
Zeolite is now being used with great success to replace sand media in sand filters. Zeolite will improve apon the filtration by filtering the water in three seperate functions unlike sand. First of all, Zeolite will filter by physical entrapment, or macro filtration, trapping the larger particulates on the top of it’s filter. Next, Zeolite will filter by micro filtration, in which the water flows over and through the porous structure. Zeolite has a greater surface area than sand. As the water flows through the zeolite’s structure, the calcium ions in the water are exchanged for sodium ions. This method
softens the water. The third filtration is through ion exchange.
