Abstract: A fluid handling cassette (24), such as that useable with an APD cycler device or other infusion apparatus, may include a generally planar body having at least one pump chamber (181) formed as a depression in a first side of the body and a plurality of flowpaths for fluid that includes a channel. A patient line port may be arranged for connection to a patient line (34) and be in fluid communication with the at least one pump chamber via at least one flowpath, and an optional membrane (15) may be attached to the first side of the body over the at least one pump chamber. In one embodiment, the membrane may have a pump chamber portion (151) with an unstressed shape that generally conforms to the pump chamber depression in the body and is arranged to be movable for movement of fluid in the useable space of the pump chamber. One or more spacers (50) may be provided in the pump chamber to prevent a pump membrane from contacting an inner wall of the pump chamber.