NEWA B Pressure filter Prexo adv. 30Pressure filter for ponds. It consists of a tank with a capacity of 20/30 liters, filter elements, accessories and fittings. PREXO is equipped with the "Backwash" system (reversal of the water flow), which allows quick cleaning of the filter without having to open and dismantle it. Simply turn the knob on top of the filter to activate the "Backwash" system. PREXO is easy to conceal because it can be partially buried near the pond. Thanks to the innovative technologies developed in Newa laboratories, the PREXO filter is able to keep the pond water clean and clear all year round.