Keep your aquarium clean and healthy with the Aqueon MiniBow Replacement Filter Cartridges. Designed specifically for 1, 2.5, and 5-gallon tanks, these filters ensure that your fish have a clean and safe environment to live in. With a pack of three filters, you can replace them periodically to keep your tank in top shape. These cartridges are suitable for fresh water and are located internally for easy maintenance. The brand Aqueon guarantees top-quality filtration for your miniature aquarium.