These filters are replacements for the filters included with the mermaid or shark aquariums.
The Marina i25 Replacement Power Cartridge is made specifically to fit inside the Marina i25 internal filter. The outside of the power cartridge features polyester foam to trap fine particles; while the inside chambers contain carbon to remove pollutants and odors; and zeolite to eliminate toxic ammonia for a cleaner, healthier aquarium environment and crystal clear water.