Keep your Fluval FX2 filter system clean and efficient with Zanyzap's 12 Pack of Bio-Foam Filter Pads. This filter media performs superior mechanical filtration, the crucial first stage in the filtration process. The foam filter pads capture large particles and are custom fit to prevent bypass. They enhance biological filtration, and are ideal for freshwater and marine aquariums. Made from high-quality materials, these foam/sponge filters are perfect for removing excess food, debris, and more from your aquatic ecosystem.  Save money without compromising function or performance.  Exclusively made to fit the Fluval FX2 Canister Filter.  Will not fit FX4, FX5, F6 models.