Unresolved I have crabs...help!!!

Discussion in 'ID This!' started by Undertheocean, Sep 17, 2011.

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  1. Undertheocean

    Undertheocean Plankton

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    Hi everyone, my name is Lexie and i have a 120 litre aquarium with Live corals, 2x clowns, 1x dottyback, and 2x yellow tailed damsels. Last night when i was feeding the fish i noticed black crabs coming out of the dead coral on one of the live rocks. I'm not sure if they are bad but i have pulled the live rock out and have given it a fresh water dip and the crabs are dead now ( i know it's mean but i've heard that they can kill your coral and anemones ) can someone please ID this crab?
    see below:

    [​IMG]

    thanks :)
     
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  3. Steve34

    Steve34 Feather Star

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    Not all crabs are bad or problematic in a reef tank. I'll give a bump hopefully someone can come in and give you an ID on it.
     
  4. sticksmith23

    sticksmith23 Giant Squid

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    I haven't found an ID for it yet, but I did find this thread on another site
     
  5. pink4miss

    pink4miss Panda Puffer

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    here is a helpful page someone posted recently that i saved Live Rock Hitch Hikers

    sorry can't remember who posted this to give the credit to, but its full off info
     
  6. sticksmith23

    sticksmith23 Giant Squid

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    I found this posted on another pic I found in google images "That may be a Xanthid crab. If the tips of his claws come to a point, then he is a probable Xanthid, if the claws look like the have a little cup at the tip then its probably a Mithrax".

    It does seem like every image I pull up that looks like what you have says that it will be a problem, but these people are only in the hobby just like us so who knows.
     
  7. 55gfowlr

    55gfowlr Zoanthid

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    Crabs are kind of like snakes. I say "Kind Of" because everything can turn around and throw a wrench in a previously figured out idea. Now, As I said, "Like Snakes", a poisonous snake has a sharp nose, where as to a non-poisonous snake has a blunt nose, or flat nose.

    .....Crabs have the same attributes, only you have to look at their claws for the answer. If they have blunt, rounded tips on their claws, they usually eat algae. If they have sharp, pointed tips, that's usually for tearing flesh and they eat meat.

    Now.....in real life, a crab is always a crab. If it gets hungry enough it's going to eat whatever is in front of it. But, we do put some crabs in our tanks because they eat certain algaes, like bubble algae, that we don't like to see. That doesn't mean they should be overlooked, or forgotten about. I personally put my emerald in my fuge because he was being a nuisance in my DT, and if I need him again, I'll just relocate it to where I need.
     
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  9. Mr. Bill

    Mr. Bill Native Floridian

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    Hi, and welcome!

    From what I can tell, it appears to be a Xanthid that actively feeds on corals.

    My motto is, "If in doubt, take it out". There's no logical reason for risking prized pets for the sake of a hitch hiker.
     
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  10. Undertheocean

    Undertheocean Plankton

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    Thanks everyone for your help! i did feel bad giving them a fresh water dip but i would be devestated if they fed off my beautiful new corals and also my damsels hide in the dead coral and i noticed that the crab tried to take a few swings at one of my damsels with his claw which freaked me out a bit. After the fresh water dip today i could only find one crab (i think there was only 2 crabs in the dead coral) however the other bigger crab must still be in the dead coral (i would assume the crab would be dead ) i have put the coral straight back in the tank...would that pose a problem if the dead crab is somewhere within the coral? i tried very hard to locate him to remove him but it was very difficult and could not even find him!
     
  11. Corailline

    Corailline Super Moderator

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    It is a dry heat, yeah right !
    If it died within the rock work you should have no issues, it's a small crab in a cycled tank.

    I would not be the least bit surprised if the crab survived a fresh water bath.

    Perhaps try a trap at night.
     
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  12. xpand

    xpand Flamingo Tongue

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    To me it looks like a Porcelain crab. If it is, it will have a second set of arms that it will use to catch debris. If it does this would make it a great addition to the set up IMO. I have one. Good luck