The AC Series takes power filtration to the next level. Built on a best-selling platform with a 40-year reputation for exceptional quality, reliability, and convenience, this series has become a standout choice that aquarium enthusiasts know and trust. Along with its proven multi-stage cleaning, CycleGuard beneficial bacteria support, and patented refiltration system, the latest clip-on generation sets a new standard for cleaning performance, media efficiency, quiet operation, and durability with several notable upgrades. Experience the unmatched cleaning power of Fluval AC Series! 4-stage filtration (2 x mechanical, chemical, biological) for superior water clarity and quality CycleGuard preserves the biological balance of your aquarium through independent media replacement, which avoids disrupting the nitrogen cycle and is essential for maintaining clean and healthy water Patented refiltration system prolongs media contact time for a cleaner, healthier and more biologically stable aquarium Direct access to chemical media – no need to remove basket from filter (less mess) Pre-filter intake strainer keeps algae filaments and debris away from pump for consistent water flow High-porosity 30PPI mechanical foam for improved filtering capability Adjustable flow control for precise adjustment Quick and easy maintenance – reconfigured media basket design offers a dedicated space for each cleaning stage, allowing for faster and simpler changes Re-engineered rotor configuration enables smoother rotations, reduced vibration and quieter operation Molded rim connection for easy installation and leveling All media included Made in Italy For use in freshwater and saltwater aquariums What's Included: Power Filter Pre-filter Sponge Bio-Foam BIOMAX Activated Carbon Available Sizes: AC20 Power Filter, 5-20 US Gal / 18-76 L AC30 Power Filter, 10-30 US Gal / 38-114 L AC50 Power Filter, 20-50 US Gal / 76-190 L AC70 Power Filter, 40-70 US Gal / 152-265 L AC110 Power Filter, 60-110 US Gal / 227-416 L