The light in his terrarium is a UVA/UVB Sunglo that works as a primary heat source during the day (the undertank heater takes over for the night) and a basking light due to its position. As I got him from a very good, family-run shelter, I know that they take new animals to a vet in order to assure adopters that their animals are healthy. I'll definitely try the oil-water mixture to see if that helps. At least he's gotten used to me rubbing scales off him, although he's (unfortunately) ticklish.

Here's hoping that in he'll get back the nice layer of beautiful scales he had when I got him!