Hitching crab, to kill or not to kill?

[azrile]

Unbeleivable how things work out.
I buy VERY small piecesof live rock. I mean the biggest single piece is probably 2.5 lbs. I purposefully did this because I didn't want anything bad coming with it (mantis shrimp etc.)
today while I am feeding my fish (flake food), this HUGE crab comes out from a piece of live rock smaller then my fist. This thing is like 2 inchs across. It is dark purple (but might just be camo'd since that is the color of it's home). I have not added LR for a few weeks and was stunned that his guy suddenly shows up and has no problem strutting around the front of the tank.
He looks kinda like the porcelain crab shown on this site :
http://64.70.152.85/porcelaincrab.jpg
But I'm not sure, mine looks a little fuller.
I dont' have much in my tank now (damsel, clown, algae blenny), but I plan on getting some corals in a few months.
Any suggestions on what to do? My hobbiest spirit tells me to let everything live until proven guilty, but I'd hate for my first victim to be a $50 coral.

 

[iechy]

I would keep him and just keep a good eye on him. If he does cause trouble it's likely that you could stop him when it starts. If you keep an eye on everything just remove him if you see anything troubling whether you saw him do it or not. I don't know much about too many crabs but I think a good many of them are safe around corals. Maybe there's a crab expert out there somewhere.HTH

 

[drillsergeant]

does he have 2 small arms right in front of his face that spread out into a fan. if he does hes a filter feeder, and not much threat to your corals.

 

[db]

Crabs are nothing but trouble in a reef tank! That is only my opinion, but I've even had emerald crabs eat corals. From the size of that one I'm sure it's going to be trouble.

 

[azrile]

Nope, not a filter eater.
I'm going to move his home to my refugium til I can make an id. Only thing I got in there is calupria.

 

[sterling]

I had a huge crab come in some LR also. Turned out to be a rock crab. He became triggerfish food at my LFS. FYI, it took me 3 days and nights to finally catch him!!!

 

[striker]

I've had tons of hitchikers come along with my lr. Snails, 4 crabs and 2 urchins. I've heard constantly that they should be removed but decided to go against it. I believe that diversity is important and beautiful in a reef tank. If the critters aren't damaging anything why remove it? Maybe they go ballistic because there isn't enough food in some tanks(micro/macro algaes).

 

[drillsergeant]

striker,
i guess i'm like you. i don't know how many hitch hickers i've had enter my aquarium. i got this one crab that is shaped like an emerald crab, but he's a sort of white and brown camouflage and real hairy. my LFS told me to get rid of it. They said it would eat my corals, But i've kept an eye out and none of the corals seem to be harmed. i've had this crab for almost a year now.