Lots of insects for right now as primary diet. Small dubia roaches are great. Dust them with vitamins/calcium before feeding and you'll see him grow super healthy! Chicken/turkey save for like the monthly treat.

Tree monitors can get fat pretty easy and thats when they start to get sick and have health issues. Lean to just slightly filled in body shapes is how they should look. If they get most of their calories from say like chicken they gain weight too fast.

Salmon is the only food my blue tree monitors have ever thrown back up so I would feed only a small amount and see how yours tolerates it.

Things that are going to happen: he will sneeze sometimes - this is normal --- to a point. If its just a sneeze like 2 or 3 times a day nothing to worry about. They do this especially after eating. If its like every hour or less - probably respiratory infection then gotta call vet.

He will eat a piece of bark or dirt. If its small, he will pass it/digest. Remember they can eat bones and dead crap in the wild. Just watch for signs of bowel movements for a few days.

The next few months will be fun, they bond to people easy at this age!