My smithii is an amazing little underwater mason. He has only been in there a week and a half, and he has already built an impressive castle.
It helps that the former occupant (The Legendary G. ternatensis, Baba-Yaga, may Neptune keep her dactyls ever-fast!) was a killing machine, and I pretty much left all of the smashed shells from the hundreds of snails that she slayed in there as building material.
-Uriel