Exo Terra FX350 External Turtle Filter The Exo Terra FX350 External Filter is designed for larger turtle tanks, paludariums or aquatic habitats and comes equipped with a spray bar for more efficient aeration. The FX350 has a duel chamber design with 1 fine foam, 5 course foams, 1 odor reducing pad, and dual carbon pads. This mix of media ensure the correct balance for high biological loads such as in turtle terrariums. Maintenance is easy and only needs to be carried out every 1-2 months in turtle terrariums and 2-4 months in other aquatics habitats.