Featuring a powerful pump, this small hang-on filter delivers an impressive flow rate of up to 66GPH, making it suitable for 2-8gallon fish tanks. High-density biochemical cotton fillings offer better breathability and less flow-resistance compared to regular sponge filters, which efficiently filter fish waste and food debris, maintaining excellent water quality. Moreover, simply rotate the water flow adjusting knob, you can easily cater to the specific needs of your different fish species. With its quiet and efficient performance, this hanging filter ensures a clean and peaceful environment for your lovely fishes.