Height

[Jamison]

How tall does a tank need to be?

[Motörcrab]

It depends on how large your crabs are and how you want to decorate. You need a minimum of 6 inches of substrate or 3 times deeper than your largest crab whatever is greater. Then add surface area for them to crawl around another 6 inches. So about 12 inches would probably be bare minimum. You wouldn't have much room to add other items such as a hides, small wheels (7.5" tall), moss pits,, or other climbing structures they would be right near the top of the tank then.

You can set up a 10 gallon tank as a bare minimum, but they do not have much ground area. Once you add two water pools, food dish, and a hide along with shells you are about out of land area. You can do less substrate for more climbing area but is not recommended.