Abstract: An aquarium water circulation system for providing improved water circulation to a saltwater aquarium by simulating a natural wave motion. The inventive device includes a container having an interior portion, a plurality of upper slots within the container, a plurality of lower slots within the container, a shaft having a first threading and a second threading, a plunger member threadably attached about the shaft and slidably positioned within the container, and a motor mechanically connected to the shaft for rotating the shaft. As the plunger member is forced downwardly, the water within the container is forced out from the lower slots and into the upper slots. When the plunger member is forced upwardly, the water within the container is forced out from the upper slots and into the lower slots simulating wave motions.