These genuine replacement cartridges fit all three Marina Slim Filter Models (S10, S15, S20), and are ideal for keeping your tropical fish healthy. The cartridges contain both zeolite and Ceramitek. The zeolite effectively absorbs toxic ammonia and reduces stress on fish, while the Ceramitek is a highly porous ceramic biological filter medium which optimizes biological filtration.

• 3 pack.
• Contains Zeolite and Ceramitek.
• Specially developed for Goldfish.

These easy-to-use disposable cartridge should be replaced every two weeks for the best results, keeping your tank happy and healthy.

Customer note: Never replace all filter cartridges at the same time to ensure a constant presence of beneficial bacteria.