If they have enough fat reserves in their tails and plenty of water, Leo's -can- go 2-3 days without eating. I don't suggest doing that, but if you can't find anyone to feed them while your gone, then just make sure to feed them adequately when you get back. As far as a week long vacation or longer, you will need to find someone to watch them while you are gone. They would definitely suffer if left for a week being unfed.