Abstract: A dual action aquarium filter has a slotted base for placement in the bottom of an aquarium. The base is covered with gravel, allowing water to be filtered through the gravel and into the interior of the base. A tube extends upwardly from the base and is connected to a filtration device containing charcoal and fibrous filter material for a secondary filtering of the aquarium water. The secondary charcoal and fiber filter is contained within a disposable portion of the upwardly extending tube. A motor is mounted on top ofo the tube and is connected to a pump impeller for circulating water up through the tubular filter. Outlet holes are provided beneath the motor for returning the filtered water to the aquarium. In a second embodiment, the secondary charcoal and fiber filter is contained in a removable filter basket disposed above the pump impeller. Water is driven up the tube by the impeller and is allowed to overflow into the filter basket.