We have a few kings and they all only get 1 mouse (of whatever size they can fit in their mouth) per week. You never want to overfeed...and in my opinion: Power feeding is a ignorant practice which endangers your snake's health.
If you are feeding 1 fuzzy a week he should be fine. You should notice that he'll poop a day or two before the next feeding...which is normally how it works. Always offer water and a place to hide.
In my experiances with kings...they can sometimes get into a mode where they have lots of energy and want to attempt to escape the enclosure or explore every inch of it. This is normal behavior and it usually passes as they get a little older...I'm not sure what you mean by that he seems hungry but if he's active a lot it's a normal occurance.
By feeding him 1 mouse a week and upgrading the size as he grows you can expect a full grown king with 1.5-2 years.....
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Chris Vanderwees
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