Thank you for the suggestions. I use 40 qt. tubs from Walmart because they have the locking lids.
I guess my biggest challenge right now is dealing with the wire shelves. Any suggestion as to what I can put on top of the shelves and somehow incorporate the heating? I do not like the wire and I feel I lose a lot of heat because of it. I was going to get plywood and lay on top of each shelf. But, the heat cable would still shift and roll when I slide the tubs in/out. Flexwatt and a thermostat is something in the near future. Doesn't the edges of that get turned up when you slide the tube(s) back and forth?

Thanks again

Josine