Abstract: Apparatus for supplying liquid from a tank (12) to an inlet of a pump (40) without interruption when the condition of the tank changes to a reversed gravity condition, includes a hollow, standpipe body (20) having a first inlet opening (26) and a second inlet opening (28). Internal walls divide the standpipe into a first compartment (32) in communication with the tank through first opening (26), a second compartment (36) which is in communication with a pump inlet port (38) connected to the inlet of pump (40), and a third compartment (42) which is in communication with the tank through second inlet opening (28). Third compartment (42) is also in communication with the discharge of pump (40) through a bleed line (46). The first and second, and second and third compartments are in fluid connection through holes (48) and (50) respectively, in the dividing walls. A vertically moveable spool (52) includes a weighted upper disc (56) and a weighted lower disc (54).