A centrifuge, including: a flange closing off one axial end of a separation chamber; a plurality of apertures that traverse axially through the flange at a radial distance from a flange axis, wherein at least one aperture is in fluid communication with a first outlet passage; a plurality of weir inserts removably disposed within the plurality of apertures to control a flow of one or more fluids from the separation chamber; wherein at least one weir insert disposed within the at least one aperture in fluid communication with the first outlet passage is changeable to prevent or allow fluid communication between the separation chamber and the first outlet passage.