You list his diet, and then say "a week". Does this mean you are feeding him a variety of foods once weekly? If so, change that to "daily".

If you are feeding daily, you are not offering enough food items. Try offering, say crickets, until he won't eat anymore. Do this in the morning. Then in the evening offer some more, or something of a different nature.

When my ornatus was very small, crickets (about 10 - 15 adults) were given around noon. Then at 6 PM two fuzzy mice were given. He grew nicely on this regimen. He's just over a year now, a little over 4 feet TL and is fed either 2 adult mice or 1 small rat daily.

You don't tell us about your setup. Is it adequate? A look through previous threads will fill you in on this.

Good luck.

Chris