I am still adjusting the design of my first melamine ball python rack. It will be for 41 qt tubs. Belly heat with 12" THG heat tape. Herpstat 1 for t-stat. It is going to hold six tubs and closed on sides and back.

This is going in my living room with ambient temps of ~70f. My question is: should I design it so a piece of insulation can fit in the bottom? I see some people put some adhered to the bottom of the lowest shelf.

Second question. Is it ok to make a groove in the middle shelf to fit the fat Herpstat probe just beneath the heat tape so I don't have a bulge for the bin to catch on?