You will need a check valve in the Aquascapes skimmer filter to hook up your pump to your plumbing. The check valve also prevents water from draining out of the bottom of the Biofalls filter and simplifies pump removal. ponddepot@msn.com Copyright - All World Rights Reserved Pond pumps, Pond Kits and Pondless Waterfall kits, Underwater Pond Lights. Aquaclearer Extreme bacteria and String Algae Buster and pond fish food. Pond Depot provides Do-it-yourself pond kits and Pondless waterfall kits delivered right to your home at great prices! Thank you for shopping at Pond Depot you online pond superstore!