Image Number 2 for United States Patent #5031572.
A box intended to be submerged within a home aquarium contains a platform for supporting small pet crabs in a dry environment. The box, completely open at the bottom, loosely fits over the platform and receives pumped air which leaks into the aquarium from below platform level. At one end of the platform is a ladder formed of a plastic sheet containing a plurality of holes that enable the crabs to climb upon the platform from the bottom of the aquarium. The box, platform and base upon which it stands are easily disassembled.