Specifications include, but are not limited to: General Carbon filters to remove chlorine from incoming city water used in our walleye hatchery system. Four filters are needed so operations can continue uninterrupted during backwashing. Each filter must be designed to handle a flow rate of 31 gallons per minute (gpm) and backwash of 30 gpm. Media Tanks Each tank shall not exceed 24” in diameter and tank height should not exceed 74”. Total height with controller not to exceed 86”. The tank volume to be sufficient to allow a minimum freeboard space of 50 percent of the resin depth for adequate expansion of the resin during backwashing. Tank to be designed for an operating pressure up to 150 psi and will be manufactured of fiberglass reinforced polyester, reinforced with a continuous roving glass filament overwrap. Tank should have a molded polypropylene base for support. Distributor System The media tank will be equipped with a hub and lateral type distributor system, with a plastic riser pipe and a fine slotted bottom distributor assembly