A control system controlling the blood flow rate in a blood supply system in which a first pump 18 is provided to transport blood for a reservoir 20 via a first passage 16 at a flow rate toward a plurality of outlets 30,26,26a of which one or more of the outlets are openable to permit flow through the outlet and closable to block flow through the outlet, wherein the control system comprises a monitoring arrangement 22 to determine a flow value representative of the flow rate through a first outlet 30 of the plurality of outlets, and a controller responsive to the monitoring arrangement, the controller configured to control the first pump 18 to maintain the flow rate through the first outlet 30 at the pre-determined level.
