Heavy-duty plastic frame with floss and carbon traps dirt effectively. Each pre-assembled aquarium filter cartridge slides easily into place, providing superior mechanical and chemical filtration, and making replacement fast, dry and effortless. Each pre-assembled aquarium filter cartridge slides easily into place, providing superior mechanical and chemical filtration, and making replacement fast, dry and effortless. The cartridge mechanically filters aquarium water through a pad of double thick polyfiber. Debris and waste particles are trapped and more pollutants removed by chemical filtration through Marineland's Black Diamond premium activated carbon. Inside the cartridge, a patented ribbed backing ensures the even distribution of activated carbon to deliver maximum water-to-carbon contact.