hitchhiker

[Steve W]

Bought some live rock today at coral reef and since I am just setting up my tank I brought it home and just put it into the tank (learning that may have been a mistake). After I put it in I noticed a small crab about 1" across and about half that front to back scurry out of one piece and then quickly disappeared. He was about the color of the live rock (beige with gray mottling) he had relatively large claws (1/4") compared to the overall body size.

Any guesses as to what he was? Is he likely to be a problem? Definitely not a hermit.

Steve W

24 gal nano

 

[Engloid]

Could be a mitrax crab. From what I have read they are usually not too bad to have in a reef tank. I think I have two in my tank. I saw them both one night, then another time saw one. Other than that, they hide very well, even at night. I haven't noticed any corals getting chewed up.

 

[reeflover101]

You might want to keep a check on other pests like flatworms, nudibranches, stuff like that. I always dip everything now. and I dry my rock out and then re cure it. To many bad things can happen. Depending on what you have in the tank

 

[MattAndKim]

There is such a variety of H/H crabs that it's impossible to say what it was. Bounce the crab ID pages at wetwebmedia off your memory, you may find it. I have gained 2 Neopetrolisthes this way and was quite pleased, very interesting to watch feed and no bother to any other tank inhabitant. I have received crabs in live rock that were absolutely not reef safe but proved to be harmless.

 

[macclellan]

+1 on the mithrax, especially if the rock is from the Caribbean, where mithrax are from.

I always dip everything now. and I dry my rock out and then re cure it. To many bad things can happen.

There's no point in buying live rock then, and that's a big waste of money (and of invertebrate diversity in your tank). Base rock is cheaper and reseeds the same as dead 'live' rock.