Fluval FX4/FX5/FX6 Bio-Foam, Replacement Aquarium Filter Media, 2-Pack, A239

• Replacement Filtration: Bio-Foam filter inserts are designed for use in Fluval FX4, FX5 and FX6 Canister Filters in freshwater and saltwater aquariums. • Double Duty: These Bio-Foam filters perform as both mechanical and biological filters. • Intricate Design: Bio-Foam’s dense structure is ideal for trapping small particles, with an intricate, porous network that provides vast surface area to facilitate biological activity. • Maintain Clean Environment: Proper filtration helps create clean and healthy water conditions. • Pack Includes: Each package contains two replacement Bio-Foam filters.