Hygger fish tank sponge filter must be used with an aquarium air pump. It is fit for small size (<15 gallons) fish tanks or fish bowls, used as additional bio filtration to aquariums. Key Features: • Included: ◦ 1x Spare Sponge, ◦ 1x Suction cup, ◦ 1x Single Mini Sponge Filter • Biofiltration, oxygenation & physical filtration to your aquarium. • Mini sponge filters integrated bio-filtration, oxygenation, and physical filtration in one • Makes small water flow, which can ensure the excellence of the water quality • Help your small fish or shrimp to live a happy & healthy life • The sponge filter is super small and takes up a little room • Fit for fish tanks or fish bowls sized from 0.5 to 5 gallons • The mini sponge filter is 3.5″ in width and 3″ in height, and the sponge inside circle diameter is 0.59 inch • Easily take down the sponge from the filter for cleaning or replacement • The sponge is fine, not coarse, which means more surface area for beneficial bacteria to live on • Don’t use tap water to clean it • Rinse or squeeze the sponges using the aquarium water • Sponge Size: 4x4 cm • Colour: Black • Size: Small • Material: ABS Plastic • Made in: China • Dimensions (HxWxD): 23x10x6.3 cm • Weight: 0.1 kg • Manufacturer's Warranty: 1-year Warranty.