A water treating apparatus is composed of an enclosed water treating chamber consisting of an enclosure wall with raw water inlets and treated water outlets, an upper plate on said enclosure wall, a flexible sheet under said enclosure wall and a bottom plate connected to said flexible sheet, and a floatage regulating bag installed to said bottom plate and communicated with an air supplying-releasing unit. Said water treating chamber is immersed in the raw water to be treated. When said regulating bag is inflated, the chamber is floating up and the treated water is drained out. When the air is released, the chamber is sunk in the raw water and the raw water comes in it. |