Shoe boxes work great for transportation, its nice and dark inside so they'll be confused but not too stressed. When i took my two adults at the same time in two different shoe boxes, when i took them out they were eager to explore. Not so eager about the meds they got once i got home for pinworms however. They fought me a bit but it worked out.
Just get a decent sized cardboard shoe box, smaller but not too small would be best, just the right size where he fills it up mostly but isnt cramped. Then put paper towels in there for him to lay/dig in.
Make sure he cant escape in any holes, but dont tape them if there are any holes as that could hurt him.
You may be able to just get a very tall cardboard box, put tons of paper towels in there and that could also work.
As for him being lethargic, not eating, and not growing it sounds like improper lighting or diet. It's still good to get him checked out by a reptile vet just in case of anything, also if your vet isn't a reptile vet and is a exotics vet make sure to research any meds they give him. Exotic vets are one of those types of things were its a 50/50 chance where you can have a good vet or a bad vet that doesn't know what hes doing for these certain animals.
Answer a few questions for me.
Is his UVB a exo terra, zoomed/reptisun, all living things, or zilla brand?
Is it a compact/coil bulb, a MVB, or a tube light?
How old is the
UVB bulb?
If tube light is it a T5 or a t8?
If tube light is it a 5.0 or a 10.0, or a 12% or 14%?
Is it mounted underneath the screen or on top.
How many watts is it?
How many inches is it from the basking spot?
What is his basking spot?
What is his warm side?
What is his cool side?
How are you monitoring these temps, temp gun/digital temp gauge/plastic gauge?
Do you use bulbs at night?
If so are they colored or produce only heat?
What type of basking light does he have?
What sized tank does he have?
How old is he?
How big is he head to tail?
How much does he weigh?
What are you feeding him for insects?
What are you feeding him for salad?
What supplements are you dusting with?
How many times a week are you dusting?
What substrate/flooring/bedding does he have?
Pictures would help greatly.
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