The invention relates to a filter device for filtering a suspension, and the method of operation thereof, wherein between a stationary head piece and a movable end piece, the filter device has a pack of a recess plate and an adjacent recess plate, the filter device has a suspension pipe for piping for piping a first stream of the suspension from the head piece into the pack, wherein connecting to the end piece, and a supply pipe for piping a second stream of the suspension into the suspension pipe, forming a filter chamber, the recess plate and/or the adjacent recess plate has a recess, from the suspension pipe, the recess plate has a suspension duct for piping the suspension into the filter chamber, and wherein between the recess plate and the adjacent recess plate, the filter device has at least one filter cloth for filtering a solid content out of the suspension.