Every crab I've ever seen, in the wild or in the store, would burrow if the sand was deep enough...Maybe the pet store has a book? We got my son an iguana one year...they were out of the book, we had to wait a week...by the time we got the book, it was too late...we didn't know that you can not feed an iguana iceburg lettuce! I had to get a second iguana...that one lived for three years, till he escaped...
if the pet store doen't have any books, find a Barnes and Noble...they will have one, it doesn't need to be a big heavy one...just basic care.
Hope this helps...Love the names, by the way! cool!
Proud Patron of Eliza's Avatar Lab!!