Petworx 45cm Air CurtainPetworx 'Air Curtain' are designed to be flexible, allowing the air curtain to be used in many different ways. The Air Curtain is manufactured from porous rubber hose allowing small air particles to form a fine mist of air accross the aquarium. The volume of air will depend on the power of the air pump used. For best results immerse the air curtain in to water before joining to the air supply.