Specifically designed for the Fluval U4 filter, the U4 Poly-Max Cartridge helps control green water and unsightly algae growth by trapping and adsorbing phosphate, nitrite and nitrate.
Features
Chemical filter media.
Produces crystal clear water, reduces odor, and creates ideal conditions for fish and plants.
Helps reduce overall aquarium maintenance.
Suitable for freshwater, saltwater or reptile environments.
