Fluid transfer device may be configured as a vacuum pump particularly suited for nondestructive transfer of fluids, including blood and blood constituents. Fluid transfer device may be used for assisting in the pumping of blood through a patient's heart for reducing the load on the patient's heart, so that sheer forces are reduced, and blood pressure on the inner walls of the heart is reduced. Pump may be used as an implanted cardiac assist device, such as an aortic assist device, a ventricular assist device, or as a complete artificial heart. Industrial applications include the pumping of fluids, including destructible fluids such as foodstuff with or without food constituents of various sizes within the foodstuff. Food and other fluids may be stored until they are dispensed. By use of a vacuum, the inventive fluid transfer device may be operated at no more than atmospheric pressure. In addition, a pre-charged pressure tank may be used dependent on the application requirements, such as in the case where fluid pressure of the pumped fluid, including the backpressure of body fluids, in the case where pressure greater than atmospheric is required to sufficiently expel pumped fluid.