I doubt it's due to husbandry issues...I spent quite a bit of time on this site and others after I first got him getting everything worked out, and he had been eating regularly for a couple months before Friday. He's almost 6 months old, the warm side of the tank is 89-92, ambient around 83. I use lights for heating and a UTH on the warm side (which, contrary to the problem that most people on this site seem to have, isn't very warm at all), with an infared light at night (so he does have a day/night cycle). He has 2 hides, a water bowl, and a fake plant in his tank. Humidity is ~50%, higher when he's shedding (I mist the tank a couple times a day...I had to soak him once to help him shed but other than that he's been fine.)
He does 'climb' when he comes out at night, which sometimes means going on top of his hides, etc, but he also just slithers straight up the glass in the corner of the tank.