A basket that is used in a pool cleaning system includes a flap that is biased closed and is opened against the bias by water flowing into the basket. When a pump drawing water out of a pool moves water through the basket, debris in the water is trapped in the basket. However, when the pump is shut off, any back flow of water associated with the pump shut off will not cause debris to move out of the basket because the flap will be shut by the bias and the backward movement of water.