A system for processing samples by a robotic platform has a tray that defines a well defining a drain. The well has a bottom surface, an access port in fluid communication with the drain, and an insert adapted to be received in the well. The insert has a bottom wall and a side wall. At least one of the bottom wall and the side wall define a plurality of openings, such that an interior of the insert is in fluid communication with the well when the insert is inserted into the well.