When I saw pictures in the Bing search of homemade hamster cages, I was dumbfounded to see clear TOTE boxes and all the neat things that goes into them! Really! Wouldn't they gnaw on that? Or its just depend on the hamster themselves? Hubby wants to use PVC pipes for tunnels, put some breathing holes along the top of the pipes when install them. Chances of chewing on them too? I know alot of the Habitat homes for hamster cages are all hard plastic. We are getting the aquarium set up and making "apartments with tubes running here and there" on the top floor to "basement". Suggestions?