Valve unit for a cistern comprising a valve housing, a water supply channel arranged in the valve housing with an inlet and an outlet, a control element, and an inlet valve arranged in the water supply channel, wherein the control element is operatively connected to the inlet valve in such a way that the inlet valve can be actuated by the control element, wherein the control element has a control rocker which can be moved between a first stable position and a second stable position, wherein in the first stable position the inlet valve is actuated by the control rocker such that the inlet valve is in a closed position and wherein in the second stable position the inlet valve is actuated by the control rocker such that the inlet valve is in a flow-through position, wherein the inlet valve has a valve chamber and a valve bore which forms part of the water supply channel, characterized in that the inlet valve also has a valve tappet, wherein the valve tappet projects from the valve chamber into the valve bore and can be moved from a closed position into a flow-through position, wherein a membrane element extends from the valve tappet to the wall of the valve chamber and divides the valve chamber into a first chamber area and a second chamber area, wherein the first chamber area is part of the water supply channel and wherein the valve bore adjoins the first chamber area, wherein the membrane element has a through hole which allows the second chamber area to be filled with flush water from the first chamber area, wherein the second chamber area has a control valve with a valve body and a control bore, wherein the valve body is formed onto the control rocker, and wherein, when the control valve is open, the membrane element with the valve tappet can be moved from a closed position into a flow-through position in the direction of the second chamber area due to the water pressure in the first chamber area. a valve housing, a water supply channel arranged in the valve housing with an inlet and an outlet, a control element, and an inlet valve arranged in the water supply channel, wherein the control element is operatively connected to the inlet valve in such a way that the inlet valve can be actuated by the control element, wherein the control element has a control rocker which can be moved between a first stable position and a second stable position, wherein in the first stable position the inlet valve is actuated by the control rocker such that the inlet valve is in a closed position and wherein in the second stable position the inlet valve is actuated by the control rocker such that the inlet valve is in a flow-through position, wherein the inlet valve has a valve chamber and a valve bore which forms part of the water supply channel, characterized in that the inlet valve also has a valve tappet, wherein the valve tappet projects from the valve chamber into the valve bore and can be moved from a closed position into a flow-through position, wherein a membrane element extends from the valve tappet to the wall of the valve chamber and divides the valve chamber into a first chamber area and a second chamber area, wherein the first chamber area is part of the water supply channel and wherein the valve bore adjoins the first chamber area, wherein the membrane element has a through hole which allows the second chamber area to be filled with flush water from the first chamber area, wherein the second chamber area has a control valve with a valve body and a control bore, wherein the valve body is formed onto the control rocker, and wherein, when the control valve is open, the membrane element with the valve tappet can be moved from a closed position into a flow-through position in the direction of the second chamber area due to the water pressure in the first chamber area.