Sand filters are one of the most popular ways to filter water.
For good reason. They are simple, effective, and require very little attention. Pool water is routed through a sand-filled
pressure vessel. Over time, dirt accumulates in the spaces between the sand particles causing the pressure in the vessel to
rise as water finds it harder to pass through. This signals you to “backwash” the filter. Simply reverse the water
flow and “knock out” the dirt.