Disclosed is a pumping apparatus (200) configured for delivering a fluid. The pumping apparatus (200) comprises a pumping chamber (220) configured for receiving one or more fluids (310, 320) in defined proportions and for further delivering the received fluids, an outlet (240), fluidically coupling to a first position (350) in the pumping chamber (220), for outleting the fluid to be delivered, and a channel (410). The channel (410) fluidically couples on one side to a second position (340) in the pumping chamber (220) and on the other side to the outlet (240), so that—in operation—a first portion of the delivered fluid as outlet at the outlet (240) is received from the first position (350) in the pumping chamber (220), and a second portion of the delivered fluid as outlet at the outlet (240) is received from the second position (340) in the pumping chamber (220). One of the first (350) and second (340) positions is a spatial position within the pumping chamber (220) where fluid components having a first property would tend to accumulate during operation of the pumping apparatus (200) if such position were not coupled to the outlet (240), with such accumulation resulting from variations in the first property.