[High Quality]: Our sponge filter is made of high quality sponge with good filtering effect. Cylindrical biochemical cotton has 360 filtration effect. Sponge filters clean dirt, stabilize water and cultivate bacteria useful to aquariums.High-efficiency filtration: Cylindrical biochemical cotton has a large filtration effect and no dead ends. It can effectively filter harmful floating objects in the aquarium, and adsorb harmful substances on the sponge to make the water in the aquarium clearer. Sponge filters are very effective at breaking down toxic waste in the tank.[General Size]: Aqua sponge filter is available in 2 sizes (3 each): Small size: 12*5cm, H*W, white tube direct 1.5cm, Large size: 15*5cm, H*W , the diameter of the white tube is 1.5cm to meet your various needs.[Easy to install and use]: Just install an air line in the device to aerate and filter your fish, increase oxygen and keep the water clean. Just connect the sponge water filter to the air pump through the air line. And the sponge can be used multiple times.[Widely used]: This fish tank aquarium soft biochemical sponge filter is small in size. The sponge filter fits in any corner and is perfect for shrimp tanks, rearing tanks, betta tanks, nano tanks, turtle tanks, fish tanks, goldfish, juveniles or other fish. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.