The Fluval U4 Polyester/Carbon Submersible Filter Cartridge combines two unique faces to perform chemical filtration, which is the crucial second step in the filtration process.
Polyester face filters fine debris and contaminants. The carbon face, on the other hand, eliminates harmful liquid substances, dyes and odors.
Polyester/charcoal cartridge providing complete and effective chemical filtration
Polyester face filters debris and contaminants
Charcoal face eliminates harmful liquid substances, dyes and odors,