Filter installation for liquids, including a basin with at least one closable suction opening, and a filter, which has a filter element and, from a removal position above the liquid can be lowered in a straight line to an operating position assigned to the suction opening. The suction opening, in an operating position of the filter, communicates with an inner space of the filter and, is connected essentially only through the filter element with liquid outside of the filter. There is a sealing device, which, during the lowering of the filter, while an external side of the filter is in contact with the liquid in the basin, seals the inner space of the filter from the liquid in the basin, so that the inner space of the filter is connected essentially only through the filter element with the liquid outside of the filter.