Aquarium fish tank air curtain for use with an aquarium air pump and air hose not includedr will create a wonderful curtain of air bubbles across your tank and due to the flexible quality of the air curtain you are able to lay the curtain out in whatever shape you wishr available sizes 45cm 60cm 75cm and 90cmr 60 75 amp 90cm sizes require a dual outlet airpump to ensure even flow