A water circulation and filtration system for maintaining a high level of water quality in aquariums is provided. Preferably the system is used in conjunction with a gravel screen, which is located just above the base of the aquarium. The inventive system comprises a vertical water flushing tube connected to a water supply or a reverse power-head pump and having an opening positioned in proximity to the base of the aquarium and below the gravel screen. A water circulation tube and water draining tube, each of which have openings located immediately above the base of the aquarium and below the gravel screen, are provided at the opposing end of the aquarium. The water circulation tube is connected at its other end to a standard filter, while the water draining tube is connected at its other end to a hose leading to a sink, drain or external container.