A cage system for laboratory animal care has a plastic cage with a removable suspended perforated-bottom, a snap-on plenum cage top and a cage top feeder lid. The removable floor of the cage has perforations that allow both liquid and liquid waste down to the cage bottom. Bedding is placed on top the suspended floor. A filtered air supply is introduced into the wall of the cage below the suspended floor and flows upward through the suspended floor through the cage in a laminar fashion and passes through orifices in the bottom of the lid and out through the filtered opening in the top. A water supply system for the cage is provided. The system is air tight and air in any one cage is isolated from air in all other cages in the system which can be mounted on a rack. Liquids drain out of the cage body possible into the plenums. A plurality of cages are supported in a rack. Several configurations to support the cage within the rack are provided.
