I'm debating that right now. I have 2 options. The first is a 50qt tub that measures 32"L X 19"W X 7"T. And the other is a 105qt that measures 32"L X 19"W X 13"T. I'm going to set-up the 105 tonight and if I mess it up I can always use the 50. The main thing I am debating on is where to put the holes. So far I'm thinking 1 row near the bottom and 1 row near the top. Then I'll have to let the tub run for a few days to see how the temps and humidity are going to hold. I'll take pics and let you know the results.
The AcuRites don't come with adhesive backing. I used Velcro. I've also got one being held on with a small bolt and nuts and the AcuRite just basically hangs on it like it would if you hung it on a wall. And it's actually easier to remove the AcuRite for cleaning than the velcro ones, and I've got pics of how I did that as well, so if anyone wants to see how I did it, let me know, and I'll post up the pics...