A pool assembly is provided. The pool assembly includes a pool body defining a pool cavity for containing water. The pool body includes an injection manifold disposed in an inlet wall of the pool body for providing a flow of water into the pool body. An ejection manifold is disposed in an exit wall of the pool body for removing the flow of water from the pool body. Removable plates attach to the manifolds for altering the flow of water. A stairway and seat subassembly is constructed of mesh is disposed adjacent the exit wall to allow water to flow therethrough.