sits next to food

For that size tub you could get a zoomed small UTH, its for a 1-5 gal I think. That one fits perfectly underneath one side of the tub. If you use aspen bedding you shouldn't have to worry about humidity, that stuff holds moisture really well.

So sticking a UTH to the bottom of a plastic tub wont melt it at all? or do I need to leave a small air gap? I know i need to get a thermostat for it and will do before setting up. Also my vet is the one that said to keep trying to feed it everyother day while on the meds just in case it decides to eat because it needs to.

Answering your first question. With the UTH plugged into a thermostat its not gonna melt the plastic. (Even without a thermostat the UTH only gets up to about 115, which is not hot enough to melt plastic, it would destroy itself if it got too hot ha)
Secondly, I'm suprised to hear that the vet suggested that. I wouldn't, the problem with introducing food all the time is 1) it stresses out the snake if it's not hungry 2) It can cause the snake to register the prey as a predator, which you don't want because then they will definitely not eat it.
Just make sure that you get a Thermostat and a Digital Thermometer with a probe to measure the surface temp of the warm side. I would recommend the ACU-RITE digital thermometer, it's awesome!

Hatchlings are nutorious for feeding issues. as someone else pointed out the smaller tub should help. I would recommend a 6qt tub. When he is over his meds try not to bother him at all for at least a week. Most hatchlings do better on live hopper mice!
You might try the bag trick......Put him in a paper bag with the hopper and roll the bag down to like an inch or two tall. Put the bag in the tub and leave for a half hour. If he doesnt eat do the same procedure with a fuzzy and leave overnight. Good luck
I wouldnt offer food every day .....Maybe weekly!

Thanks. Ordered a thermostat (on off type johnson i think) and some flexwatt, picked up 2 12 qt tubs drilled a few air holes in one gonna get that all set so when its off meds i can leave it set up all alone for a week. Now i have a question about the tub. obviously the heat is gonna dissipate real quickly anytime i remove the lid to change water or what not. Do they heat back up pretty quick? I've noticed that it takes a while for the tank its in now to recover after i uncover the top and open for more than a minute or two.

You'd be suprised how little heat does escape when you open the tub. And if any does, it should jump right back up in no time. A lot of people use tubs in their racks and don't even use lids.