Well...you could always switch to a slightly bigger tub or, as I think a few people suggested in your "Rate My Enclosure" thread--just use a smaller water bowl. If you did that, two hides would be possible... I don't think that switching to a tank is strictly necessary...but ultimately, I guess that's your decision. If you prefer tank asthetics and are prepared to tweak it to get the right heat gradient and humidity, then I don't see why not.