The system has a metering unit for metering a medium (2) and a feeding unit self-primingly connected with the metering unit for inletting the medium and for feeding the medium to the metering unit. A cover (3) connects the feeding unit and the metering unit with a container (1). The feeding unit and the metering unit are formed by a spiral pump (4) and a gear pump (7), respectively. The spiral pump is formed by rotating in a tube (6), and a snail (5) is aligned in perpendicular to a surface area of the medium. The snail penetrates the cover of the container.
