A load suspension and weighing system for a removable reservoir unit of a portable dialysis machine includes a centrally located flexure assembly. The flexure assembly includes magnets and a number of flexure rings which allow for movement of the magnets about a fixed circuit board. Sensors in the circuit board sense changes in the magnetic field as the magnets move in relation to the circuit board. The magnetic field changes produce a voltage output which is used by a processor to generate weight calculations. The top of the flexure assembly is attached to the interior of the dialysis machine. The entirety of the reservoir unit is suspended by a first internal frame that is attached to the bottom of the flexure assembly. Having a single flexure assembly positioned above the reservoir unit provides more accurate weight measurements while also preventing damage to the assembly from water spillage.