Abstract: A vivarium system for use with an aquarium is described. A closed container adapted to fit on an aquarium with a hole in the bottom planar member of the vivarium allows animal access from the vivarium into the aquarium underneath when used in conjunction with an aquarium. The container may be provided with condensation control and/or lights. In some embodiments the vivarium further comprises stands to assist in the animal transition between the aquarium and the vivarium. In further embodiments the vivarium/aquarium assembly is connected to a tidal flow control mechanism, which allows for the cyclical raising and lowering of the water level in the aquarium.