Air Driven Sponge Aquarium Filter Double Biochemical Sponge Ultra Quiet Filtration Aeration Cultivate Nitrobacteria Adjustable 16.2cm-21.2cm The sponge filter provide both mechanical and biological filtration, traps floating debris and protect your baby fish from being sucked up into the filter, multi-layer filtration design, can cultivate beneficial nitrifying bacteria. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. Features: 3IN1 AIR POWERED SPONGE FILTER:Filtration, aeration and cultivate nitrifying bacteria in one solution, keep the water well oxygenated, works great without noise. Encourages the growth of biological colonies and holds large amounts of good bacteria. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. HOW TO WORKS:Connect to air pump, which is the power source, combined with the sponge filter. The principle of biological filtration is e multi-layer filtration to cultivate beneficial nitrifying bacteria. The sponge can absorb fine particles to achieve the effect of purifying water. The water flow is controlled by airflow, which is small and slow and does not affect fish. DOUBLE MULTI-LAYER RIBBED SPONGE DESIGN:Multi-layer filtration design, it quickly established a biofilter, two sponges mean more surface area for beneficial bacterial colonization and faster Cycle, keep your fish tank crystal clear and clean. Rotatable filter sponge, adjust and filter dirt at different water levels to suit your fish tank water level. EASY TO SETUP:Use a 4mm air hose to connect one end to the air pump and the other end to this tank filter. The outlet tube in the sponge filter can be adjusted(16.2cm-21.2cm) so that you can change the direction and height of the water flow. Great way to clean and oxygenate your tanks. EASY TO CLEAN:simply take out the sponges, rinse and squeeze them in tank water, remember to clean the sponges every 3 months and replace regularly. Easy e: Comes with 2 suction cup, can be installed anywhere.  WORRY-FREE WARRANTY:If there are any problems, please contact our store in time. We will give you a 100% satisfactory solution. Thank you for your understanding and welcome next time. Specification: Item: Aquarium sponge filter Main color: Black Function: Filtration, aeration, cultivate nitrifying bacteria Main material: Food grade silicone suction cup+filter sponge+ABS Optional type: 7 types Optional size:  *Cotton body 4.8 * 6cm, product size is not stretched 9.5 * 12.5 * 4.8cm, suitable for fish tank 20-30cm;  *Cotton body 4.8 * 8cm, product size is not stretched 9 * 13.5 * 4.8cm, suitable for fish tank 30-40cm; *Cotton body 4.8 * 8cm, product size is not stretched 14 * 16.2 * 4.8cm, suitable for fish tank 40-50cm; *Cotton body 4.8 * 11.8cm, product shape is not stretched 16.5 * 23 * 4.8cm, suitable for fish tank 50-60cm; *Height include plastic tube 15.5cm, diameter 7.5cm, sponge height 6.3cm, suitable for fish tank below 40cm;  *Height include plastic tube 16cm, diameter 12cm, sponge height 10cm, suitable for fish tank below 60cm;  *Height include plastic tube 20cm, diameter 12cm, sponge height  11cm, suitable for fish tank below 100cm;  Note: Usually, sponge cleaning time is 3 months. Do not use soapy water or other cleaning solutions to clean the sponge. The sponge can't be washed too clean. Rinse with fish tank water is ok, because there are nitrobacteria in the sponge. If you wash the sponge too clean, it will destroy the nitrobacteria. Package Information:  Package size: 17*21*5cm Package weight: 65g Plastic Package Packing List: 1* Aquarium sponge filter