Air Operated Small Corner Filter, Air Driven Bio Aquarium Fish Tank Filter Air Operated Internal Small Corner Filter, Quiet filtering system. Perfect for small aquariums up to 15 gallons. Air Driven Bio Corner Filter Sponges with gravel and bio rings. Comes complete with gravel, bio rings and two layers of sponge filter foam as filter media. Bio-sponges and gravel work as a biochemical filtration and support colonization of beneficial bacteria. Each unit requires an air pump and airline tubing to operate together (sold separately, not included). Easy to maintain. Just take out the sponges and rinse well when it becomes dirty. Air Operated Internal Small Corner Filter Fits standard aquarium fittings. Especially good for breeding small fish. ? Size is 3 Inch on Square Corners, 4 Inch Across Front ? Gravel Filter Sponge Filter Media, Included ? Adjustable uplift tube to 7 Inches ? Quiet Filtration, simple and effective ? Needs air pump and standard airline fittings to operate (Not Included) ? Wash in water prior to using in aquariums We sell many aquatic products online, check out our store! Terms and Conditions. We use all approved methods for accepting payment. Sales Tax will be added to all shipments based regulations. We always try to combine purchases, please contact us directly for a personal service. You will be notified on the day that your goods have been dispatched via e-mail with tracking which is used on all purchases. Please note that if there are any problems, contact us first via e-mail giving full details of any problem along with your user ID. We use USPS and UPS as our chosen carriers shipments to Hawaii, Alaska Puerto Rico may incur surcharges, contact will be made to advise before shipment at which point the order can be canceled if desired. Orders placed on Saturday/Sunday Public Holidays will be processed next working day. We pride ourselves on excellent feedback, if any part of the buying experience is not to your satisfaction, please contact us to rectify before leaving feedback. By committing to buy you are agreeing to the Terms Conditions stated above.