PROBLEM TO BE SOLVED: To provide a filtration device capable of reducing a space of the whole equipment of an aquarium, having an excellent silent property with a small operation sound, and having a favorable filtration capacity.SOLUTION: The filtration device includes a filtration chamber to which aquarium water as a filtration target flows. A part of a constitution wall of the filtration chamber is formed by a filtration filter 5 including a filter material, the filtration filter 5 attached detachably to the filtration chamber. A front face wall of the filtration chamber is formed by the filtration filter 5. By bringing the filtration filter 5 into an inclined state on the front side from the lower side toward the upper side, the attached state can be cancelled, and the detached filtration filter can be pulled out toward the generally upper side.SELECTED DRAWING: Figure 4
