Check the complete filter designation before ordering and compare it with the compatibility information on the product page. Replace or clean only the appropriate media so that established biological filtration is preserved wherever possible.
Fluval filter cartridges for the correct filter series
Fluval replacement cartridges and filter inserts are designed for specific internal and external filter series. This selection includes mechanical foam and fine fleece as well as biological, activated-carbon, ammonia-, nitrite- and phosphate-removing media.
Choose every insert by the exact filter series and model. Products for FX filters, the 04/05/06/07 external-filter generations and the Fluval U internal-filter series differ in size and construction and are not automatically interchangeable.
Standard foam, fleece and biological media support routine filtration. Chemical media have a defined purpose and should be used only when required, following the product instructions and the measured aquarium conditions.