Abstract: A filter apparatus connected a container, where the container includes a container neck and is filled with a filling material. The filter apparatus includes a filtrate riser tube in the container, which extends from the base region of the container to the container neck, a container connector head, which is fastened to the container neck and defines passages connected to a liquid inlet line and an inlet filter, and a connector unit with a sealing piston in the connector unit, which is arranged so as to be lowerable to connect the liquid inlet line to the filter material in the container and the filtrate riser tube to the filtrate outlet line.