Abstract: A gravel vacuum including a suction tube, a pre-filter tower connected to the suction tube, a filter tower, a return assembly, a pump, and an alternate flow path with a flow control valve. When the suction tube is placed on gravel under water, the pump impels a flow of water and gravel into the suction tube, impels the flow of water and at most a portion of the gravel into the pre-filter tower where the portion of gravel is pre-filtered from the flow of water, impels the flow of water into the filter tower where the water is filtered, and impels the flow of water to the return assembly. The flow control valve controls a flow of water that bypasses the pump, thereby permitting adjustment of the flow of water and gravel impelled into the suction tube. A second flow control valve can be located near the suction tube.

Abstract: A gravel vacuum, including a pump, a detachable suction base connected to the pump to which a suction tube can be attached, a filter connected to the suction base, a return assembly, at least one valve, and an alternate flow path. The pump impels a flow of water from the suction base, through the filter, and out the return assembly. The valve permits adjustment of volume of the flow for different sizes of fish aquariums. The alternate flow path reduces back pressure on the pump when the valve is used to adjust the volume of the flow. Also, a method of using the gravel vacuum.