The EBF 6,000 Biological filter media offer tremendous surface area for beneficial bacteria to colonize and grow. The patented media never needs replacing. This filter is the perfect replacement for the Aqua Ultraviolet units. This filter in conjunction with the included media is designed for high flow rates without channeling or adding additional head pressure. Low maintenance just turn valve system to backwash and clean filter means never having to mess with dirty mats. The Evolution Bio Filter works great with low amp, high flow pond pumps.