Fluval U4 Underwater Filter Poly/Carbon Cartridge

Fluvial poly and carbon cartridges features two sides for effective chemical filtration, the crucial second stage in the filtration process. The polyester filter pad side filters out fine debris and contaminants. The carbon side filters out harmful liquid substances, colorants and odors. The Fluvial poly and carbon cartridge works in part with the Fluvial filter foam pad to help keep your aquarium healthy and clean.