I wouldn't recommend it, personally. Beaded lizards, and heloderms in general, require much more humidity than most would expect. Plus, as you've discovered, sand is messy and gets into every crevice. It can end up causing irritation that can lead to infection in the cloacal region. Most people keep their heloderms on the following subtrates: Sani-Chips, Cypress Mulch, Newspaper, or Care-fresh.