In my experience tubs are fine if the room does not get below 72ºF (76 is better) if it does it will need a secondary heat source of some sort. Tubs have a very limited heating options. I love pvc enclosures easier to heat and manage than any open top aquarium, rack, or tub I have ever owned. My fist choice is PVC type enclosures then the side turned tank rack if you have no space, tub, and tank open top.