Crab on LR

[jflowers]

Got a huge chunk of LR yesterday, lots of crevices and holes for good and bad little critters to hide. Was just admiring my tank and noticed a crab in one of the holes, not a hermit but the usual kind about 3" accross. soon as I moved it shot back in the hole so cant get a pic. The LR is pacific LR. Is this likely to be a pest crab or beneficial?

Tank stats in my sig.

Jon

 

[chkltcow]

Does it look like anything on this page: http/www.liveaquaria.com/product/scateg....01&TopCatId=501

Chances are it's not a pest, but it's hard to say without seeing it.

 

[jflowers]

Nope, none of them, it looks more like the kind you can buy in the supermarket to eat. It has black claws and red legs.

Jon

 

[Navarre]

try and get a look at its pincers.
if they are spoonlike then its most likely a safe algae eater. (But will still take opportunistic chances)

If they are like scissors then they are predatory

 

[jflowers]

They are like scissors + he sits in his hole as though he is waiting for a fish to swim by rather than graze on the large amount of algae that came with the LR. I have also seen a couple of live shrimps swimming around this morning and a large number of copopods (Spelling?) on the glass.

Thanks for the replys so far. Should I remove the crab? I dont want to risk fish yet. I will grab my dads camara when I go round for lunch so look back later.

Jon

 

[jflowers]

Finally got a pic of this monster, posted in this thread...

http/www.fishforums.net/index.php?showtopic=73927

Not the best pic, but the best I am going to get. Any ideas?

Jon

 

[Navarre]

Looks like an acro crab to be honest. Dont know how it got on the liverock though. Acro crabs are safe but they stay within the branches of acros so they are no trouble really. If its not an acrao crab then all i can say is that all crabs are opportunists and wiol try to grab an easy meal if and when they get the chance.

I would keep a close eye on it

 

[jflowers]

It got in because the 6.5kg lump of LR I bought was full of 'caves' And it was in one of those. That was the main reasoon I chose that particular piece, the caves, not the crab LOL.

I have been keeping an eye on it, and it flinches away when fish go near it. It moves very fast and have seen it grab brine and mysis shrimp as they float past. I will now go and google that acro crab.

Thanks Navarre

Jon