Abstract: The disclosure provides a cell culture well tray assembly having a reservoir plate for containing cell culture media, a removable tray structured to fit on top of the reservoir plate, having a top surface and an opposing bottom surface defining a deck, and a plurality of well apertures in the deck, at least one removable well, structured to fit through a well aperture and extend below the bottom surface of the deck of the tray, each well having a well enclosure for containing cell culture material and a hanger, wherein when the removable well is inserted into a well aperture, there is a space between the deck of the tray and the hanger of the well.