Ok well I want to build a rat rack, but I don't want to use mortar tubs. I feel for some reason that there isn't a whole lot of running room. I have mine in big sweater bins. I have them proper outfitted for ventilation and what not, and with food hoppers. The problem is that they are kind ugly and are cumbersome, and some are starting to chew out. I want to build some kind of rack but I was looking for some ideas in terms of the tubs that I could use that are slightly longer, and slightly taller. I don't want to use anything that is too big because size does matter. Lemme know if you guys got any ideas.