I life in Kuala Terengganu and have spotted quite a few Hermit Crab in the wild.

If I were to adopt this cute guys, how would I need to setup the tank?

Do I need to have both water (salt water) & land (sand) on the same tank?

Because in the wild, I see them walk around in under a big tree, then into the water (salt water river) ... just constantly walking around...

I also need to provide them with new & bigger shells as well as fresh water right?

Just wondering, where do these crabs get their fresh water supply in the wild? Since its just salt water all around them.

Better to adopt them in pairs or in a colony (a few of them) ?