I will just give you a little reminder, that the hammock you chose is a good one, but I found that the straw molded, and the crabs loved eating the straw. I had that exact hammock, and it was destroyed in under a year, they always wanted to eat it!
![Smile :)](./images/smilies/icon_smile.gif)
I personally would have gone for a larger tank though, as this one is square, and it has swinging doors, that prevents the substrate from going higher as you need it to be.
If you have smaller crabs, it'll be just fine for a while.