>>I am going to follow your recomendation and experiment with the Light Ropes and see how that works out.
Or look at it this way. If you end up builing another rack you know you'll be heating it with the heat rope, so perhaps go ahead and order that for your current rack. You can always use it if you trash this one.
>>a couple questions; where do you buy your tubs at? Is there a certain brand you recomend over the other?
I much prefer the Rubbermaid 28 qt. and 12 qt. boxes, especially for the smaller Triangulum ssp. you keep.
I find them to be a bit more sturdy and I also like that the 28 qt. and 12 qt. boxes are the same height.
Sterilite makes two versions each of their 28 qt. and 12 qt. boxes. One with raised feet, the other with a continuous rim around the bottom. I have found the one with individual raised feet to be less secure.
Unfortunately the 12 qt. in one of the types is just a hair shorter so there are minor security issues. A bigger deal with the species you keep.
Sterilite does make a 32 qt. and 13 qt. version that are very nice and sturdy but they are tall enough that you can only fit 6 levels in a 4' tall rack assuming you're using 3/4" thick shelves.
With the rubbermaids I can fit 7 levels in a 4' tall rack. A nice feature since lumber comes in 4' increments.
I buy my Rubbermaids at Menards. They were recently re-released so they should be available.
I build all my rack so that the 28 qts. slide in width-wise. That way two 12 qts. can fit in length-wise on the same level.
Here's a picture of a rack I built for $40. You can see that on some levels there are two smaller boxes.
In this picture I was only using the rack to store supplies and mealworms, no snakes.

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Current snakes:
0.2 Gonyosoma oxycephala - (Silver/Yellow)
3.3 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)
3.3 Gonyosoma janseni - (Black & Tan)