Hitchhiking crab

okay so I started a tank back in June, got my live rock and everything's been great.... then today I'm looking and all the sudden see this fairly big crab hanging out. I got the best picture I could , I'm curious if anyone knows what type of crab it is and if so could they give me some info. I know in general crabs are aggressive and I'm a bit concerned but my cleaner shrimp and watchman goby have been in the tank(small tank) for months so maybe no need to worry? Anyway here's the picture, its a grey/greenish colored crab



 
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If it's is an emerald , would you suggest removal?


I know there's been numerous debate on emeralds , I myself am very wary of crabs
 

2quills

Well-Known Member
I'm not a big fan of them personally especially if you have a reef tank.

But they have been known to kill other inverts like cleaner shrimp from time to time from what I've heard.
 
thank you for the response, i really appreciate it, im lucky that so far my cleaner shrimp has been fine but i may try to remove the crab, i'm just not sure how as of yet.
 

one-fish

Active Member
When I was young we went crabbing with string tied to a raw chicken neck and a crab net but that was for Blue Crabs....Lol
 
i was thinking about putting shrimp in a jar and when it climbs in it wont be able to climb out but i have a feeling it wont go for it.
 

one-fish

Active Member
Worth a try just don't leave shrimp in to long I have also found it a pain to catch a fish ended up rearranging rocks so I could divide tank in half finally caught it. BTW some say emerald crabs are beneficial but it's a crab and they are opportunistic feeders
 

one-fish

Active Member
Was researching them to help my GHA is back bought 12 more nassarius snails instead needed more sand sifting critters Read Emerald crabs will eat bubble algae and other nuisance algae and if fed are safe but a crab is a crab...my clowns lie down on their sides at night and sleep together...
 

florida joe

Well-Known Member
I have an emerald in my reef tank, what you want to make sure is that the pinches on your crab are rounded and do not come to a point
 
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