And I have read that they are generally peacefull with the exception that if you keep two you will need a fairly large tank as they may be aggressive towards their own kind. However, I was watching him trying desparatly to pull a small blue legged hermit from his shell - at that point I was starting to get concerned. After about 30min he gave up and the hermit went back to work cleaning my rock. I was relieved at that point. I have been watching him since.
This is definatly a arrow crab - exact same as the smaller but this guy is huge. If you were to spread his legs out flat, he would probably be about 10" wide. His pointy head is about 2-3" long. maybe he's a freak
