I think that the 4'' heat tape works well for this size tub. I did notice that Sterilite took the 1756 off of there website so I need to get to the store and pick me up some extra's. I think the only thing I would change would be when setting up the spacing in-between the tubs. I used 1/4 piece of mdf cut close to the same size as the shelf. If I did it again I think I would use 3/16 Hardboard. I used 3 dvd's under all the tubs the first time and all the shelves were to tight. I thought the 1/4 was good but the space is just a little too much and the snakes like to rub their nose along the tops of the tubs. I shimmed the bottom fronts of the tubs with round pieces of felt and it works great. If you are going to build one please read all my posts in this thread and ask any questions you want I will try to answer. Also see my other thread, the completed rack. http://www.ball-pythons.net/forums/s...ad.php?t=58302