Fluval Poly/Clearmax filter cartridge helps control green water and unsightly algae growth by adsorbing and trapping phosphate, nitrite and nitrate. It effectively produces crystal clear water, reduces odors, and creates ideal conditions for fish and plants. The filter cartridge helps reduce overall aquarium maintenance.
It is ideal for freshwater and marine environments and designed for Fluvals U2/U3/U4 Underwater Filter. Contains 2 cartridges.

Also available :

A490 Fluval U2 Poly/Carbon Cartridge
A486 Fluval U2 Foam pad
A495 Fluval U2/U3/U4 Biomax,