Abstract: This is a swimming pool water exchange device. It allows the complete changing of the water of the swimming pool without draining the pool. By filling a giant bag or bags at the same time as the heavy water, at the bottom of the pool, is drawn then pumped out, a complete or near complete water exchange is possible. It uses the water seeking its own level effect to create a self-regulating exchange system. It does this by incorporating a second container separate from the pool. By placing a pump in this second container, a very low pressure flow is created going from the bottom of the pool, to this second container. The pump, in the second container ejects the water, from the container, at a predetermined height. When the water rises above this height, the pump greatly increases its pumping action. When the water falls below this predetermined height, pumping ceases. This allows the water bags to fill as slow or as fast as the supply hose can deliver.