This black silicone for ponds is used when installing a Aquascape Designs skimmer filter or Biofalls filter. 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!