A cell culture apparatus includes a cell culture module including multiple cell culture chambers. A manifold connects the multiple cell culture chambers together along a side of the cell culture module. The manifold includes a side wall base structure connected to the side of the cell culture module and a column structure that is formed as a monolithic part of the side wall base structure. The column structure defines a fluid flow pathway through the manifold and to inlets to the cell culture chambers to allow filling and emptying of the cell culture chambers of liquid medium.