The EHEIM Aquarium Prefilter can help you improve the filtration process for the benefit of your finned buddies. It is designed to help avoid clogging in canister filters and can be easily installed onto your existing setup with its base securely on the bottom. Drawing water from a wide surface area， it traps dirt， debris and waste in its enclosed filter baskets to optimize the biological decomposition process and reduce the need for regular maintenance. The two filter baskets each contain a cartridge of their own to keep removal and cleaning easy and convenient.