Is it a tube that you've got in the repti-sun 10.0? If so definately change it immediately. The repti-glo as everyone has said is really bad for their eyes, it also can reduce colour, appetite and activity.
Are you using a bright white basking bulb? This can also hinder appetite and activity. And are you
bathing regularly? Them being kept
hydrated is really important also. You should be
bathing every other day for 20 mins, in lukewarm water.
Are you offering crickets 3 times a day? and are you leaving it about an hour or two after the lights have come on before offering? If he is only eating that little and not everyday, I am concerned that he will not be getting enough supplements - calcium and vits. Do you dust his veggies as well as his livefood?
Also mealworms aren't great for their digestion system and don't actually offer that much protien. I would stick to crickets, locusts and roaches, or phoenix worms are great for babies and contain their own calcium so don't require dusting. Also silkworms - any soft bodied worms rather than mealworms because they have a hard chitilin shell. Waxworms are also great for a treat - but they're quite fatty, useful for putting on weight.
Hopefully you will see an improvement when you change the lights over.
Good luck, and let us know how it goes.
Nikki