Aquaclear 110 Replacement Media Bundle: Sponge, Carbon, Ammonia Remover Contains 1 Activated Carbon, 1 Foam insert, and 1 Ammonia Remover insert Ammonia Remover is ideal for new or heavily populated freshwater aquariums Activated Carbon Filter Insert improves water clarity in fresh and saltwater aquariums The Foam Filter Insert is a mechanical filter media that effectively removes particles and debris from aquarium water Each of these filters are exclusively designed for use in the AquaClear 110 Power Filter to help reduce stress in your fish, eliminate odors, discoloration and impurities in your aquarium