Roborovskis like to run in wheels a lot and if you have more than one robo in a tank, usually more than one will want to get on at the same time. This can be quite comical but you might also want to get more than one wheel in this case. Without their wheel, they might become quite restless and start to run the length of their enclosures and jump up and down along the sides.

Video Clips

Roborovskis running on their wheel