^
Where's your location?
Just incase some of you can't get beach sand, you may use crushed corals as well. Ask for the smallest grade, if not mistaken is 3. hermits love to burrow inside it. Reusable and cheap compared to beach sand.

For calcium can use cuttle bone. Pets shops selling birds might have them. Or you may be lucky to find some on the beach as well.

Forgot so many terms.. Haha, long time never keep crabs already.

bee002: The small one you have behind the straws is an Ecuadorian or a Rugg?