Filter (aquarium)
（重定向自Aquarium filter）
![Air-driven corner filter](/Images/godic/202412/21/Corner_filter3719.jpg")
![A large shower biological filter designed to maximize the beneficial effects of the nitrogen cycle, in a koi pond](/Images/godic/202412/21/KoiPondTrickleFilter3719.jpg")
![Sponges, plastic balls, ceramic tubes and gravel are all suitable for aquarium filtration](/Images/godic/202412/21/Filtermaterial_0602273719.jpg")
![A commercially available canister filter](/Images/godic/202412/21/Aquarium_-_external_filter3720.jpg")
Aquarium filters are critical components of both freshwater and marine aquaria. Aquarium filters remove physical and soluble chemical waste products from aquaria, simplifying maintenance. Furthermore, aquarium filters are necessary to support life as aquaria are relatively small, closed volumes of water compared to the natural environment of most fish.