Yeah, you will need to add heat tape to the floor of the cold side if your RHP got to 100+ and was running full power 24/7.

As for your boa looking thin, its only one pic but to me, it looks fine. It has the nice muscle line running down the side of its body. Looks like it should be on weaned rats but again hard to judge from a pic. Keep the food item same thickness or slightly thinner than the snake and if it is anything above mice, then once every 2-4 weeks. I do every 2 weeks for weaned/small rats, 3 weeks for medium rats and 4 weeks for large rats.

And your snake doesnt look round to me. It does look hypo ad from what i have been told, hypos can look more round but that is just the nature of hypos. You want to make sure the top of the back is fairly flat. Boas will store fat on either side of the top of their back so if your boa has what looks like the Grand Canyon down its back with the bottom of the canyon being the spine, then your boa is overweight. Also like i mentioned, you want to look for the nice muscle line down the flanks of the animal which yours has. It is very hard to underfeed a boa. Snakes are designed to go months without food in the wild and often do as well as going 3+ months without food normally in the winter.

And thanks, I do love my suri.

If you have ever seen a truly starved boa, you can clearly see it. I would bet over 75% of the people who own boas overfeed them, myself included when i first got into boas. They always act hungry so you think they need to eat.

Anyways, to give you an example, here is my 4 year old sunglow and you can see she kind of looks round in the pic but she was getting a medium rat every 4 weeks. She just recently got upsized to large rats every 4 weeks.