HAYWARD SAND FILTER - PRO SERIES - TOP MOUNT - 21" (COMPLETE)

Hayward Pro Series high-rate sand filters offer the very latest in pool filter technology with smooth efficient flow and totally balanced back washing. Pro Series sand filters feature unitized construction of corrosion-proof polymeric material and self-cleaning 360? slotted laterals. A versatile seven position control valve offers both easy operation and maximum efficiency. For crystal clear sparkling water with minimum care Pro Series filters set a new standard for performance valueand dependability.Sand filters are one of the most popular and cheap way 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. In this method impurities are extracted from the water using sand to collect and attract the debris as small as 20 to 40 microns. Over time dirt accumulates in the spaces between the sand particles causing the pressure in the vessel to rise as water finds it