Hi Craig - Yes regarding the skull that makes sense, he could get stuck if he tries to go in. I may either fill the inside with something so he can't try to go in or remove it.

I am going to go pick some terrarium backgrounds / tank liners and cover the back and sides + pick up a few things which can add some more clutter- this will make him feel much more secure.

I do have a thermostat and have set it regulate at 44C. The sensor is placed between the UTH and the glass and from on top of the substrate im getting a reading of 29 - 30C in and around his hide which is his hot spot. Will also pick up an identical or very similar hide for the cold side - good suggestion.

Thanks for the advice