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.
Note : For best results replace every 4 weeks.
Key Features :

2-pack
Provides mechanical, biological, and chemical filtration
Polyester foam traps fine debris; carbon removes pollutants and odors; and zeolite eliminates toxic ammonia
Easy to replace
Designed to fit the Marina i25 Internal Filter (A131),