arrow crab experiences?

[Kigs]

Does it always come down to bad news with arrow crabs? I really want to keep one in a 29g, but I've heard bad news about fish killing and etc.

[Beerven1577]

first time I ever went to petco they had an arrow crab and it was going to town on a little blue fish (damsel?) and eating it, my buddy and I were laughing because the fish cost more than the crab. I would probably stay away from those