Superfish Air Sponge Filter Superfish Air Sponge Filter – A simple but very effective biological filter for small aquariums. Simply connect the filter to an air pump to use. Useful bacteria attaches to the sponge providing biological filtration. Available in: Small Extra Large (XL) SuperFish surely makes your aquarium hobby successful, complete with aquariums, filters and filter media, heating, lighting, ventilation and useful accessories. It is our goal to make your aquarium hobby successful and also affordable. Click here to also browse a wider range of Pumps & Filtration products we stock!