Our Petco Power Filter offers more control and convenience with a quiet, self-priming submerged pump for instant water flow. The benefit of an internal pump is that when it is plugged in, the pump will automatically start the flow of water through the filter. This is critical in the event of a power outage or interruptions. The filter will automatically start up when energy is restored. This power filter also boasts silent operation. Motor noise is reduced with pump submerged in water. The only sound is that of a soothing flow of water into the aquarium. The filter features internal biological ridges that extend from the spillway all the way to base on the inside of the filter housing for maximum biological filtration with minimal noise. This power filter includes a filter cartridge with activated carbon to aid in water clarity. The 3-stage filtration will exceed your expectations and keep your tank cleaner than ever. The filter cartridges remove discoloration, odors and impurities that are unhealthy for your pets and can turn your beautiful aquascape into a cloudy mess. These filter cartridges use mechanical filtration with the high-density floss to capture debris and particulates. Chemical filtration is provided by the activated carbon and biological filtration occurs through the built-in biological grids which allow for beneficial bacteria growth to remove ammonia and nitrites. These filter cartridges are designed to be easy to insert and replace. The activated carbon media is embedded in the filter floss and will provide the appropriate amount of mechanical and chemical filtration under normal conditions for 2 to 4 weeks. No need for multiple layers of media to achieve desired results. You can help keep your fish tank crystal clear by replacing the filter cartridges every month and not overfeeding your pet fish. Convenient guides hold the filter cover when changing the cartridge.