In an appliance for filtering liquids, in particular waste water, with filter discs lying on top of one another and forming a flow path for a liquid to be filtered, wherein the appliance has at least one device for generating a movement of the filter discs, provision is made that the filter discs have means by which mutually adjacent filter discs are connected to one another with a form fit, these means being assigned to at least one circumferential portion of the filter disc. In particular, the means for form-fit connection are assigned to two mutually opposite circumferential portions of the filter disc.