What tank mates for this guy? Also, ID?

[VFX]

I've had this crab in my refugium for a long while but now's time to give him a proper home as he's getting a little lonely.

I was thinking of setting up a nano for him. Something like a 14G or so.

Just looking for ideas for tank mates baring in mind he's now about 4-5 inches in size.

Also, anyone know exactly what kind of crab he is? I bought him as a swimming crab...



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