🐟 25% MORE ACTIVATED CARBON - Aqueon Replacement Filter Cartridges are dual-sided, featuring dense-floss with over 25% more activated carbon than the leading brands. 🐟 HIGH-QUALITY ACTIVATED CARBON - The cartridge contains high-quality activated carbon that keeps water clean. 🐟 EVEN CARBON DISTRIBUTION - Aqueon’s patented cartridges were designed to ensure the even distribution of activated carbon. 🐟 EASY INSTALLATION - Simply rinse under cold water and easily install using the "FRONT" orientation tab. 🐟 MULTIPLE SIZES AVAILABLE - Aqueon Replacement Cartridges are available in X-Small, Small, Medium, and Large. 🐟 OPTIMAL PERFORMACE - For optimal performance, change approximately every 4 weeks. 🐟 VERSATILE - Fits Aqueon QuietFlow Filter: LED PRO Size 20, 30, 50, and 75, Power Filter Size 20, 30, 50, 55/75, E Internal Size 40, Canister Filter Size 200, 300 and 400 🐟 TRUSTED - Developed by true aquatic hobbyists, Aqueon provides a broad array of aquarium solutions to help maintain healthy, life-sustaining aquatic environments. From inception, Aqueon had one goal in mind: “Doing what is best for the health and well-being of fish and aquatic life.”