Marineland 24-Pack Penguin Rite Cartridge, Size C

excellent products ,used the before and will continue to use them Quick delivery,on budget price.Trusted product name brand,Great buy for all.

These are pretty good. I use two in one filter. Or four in a double sided filter. Two on each side. To help clear your water even more.

Needs better packaging when buying these large quantities

Great Deal! a 3 pack at PetSmart is $13, ordered and found this to be a cheaper solution and well worth it.

Very happy great product.

Used non genuine filters. They never work as well as the original filters. This was good price for over a year supply.

Need plenty of threse around. Have a large aquarium.