Emerald Crabs

[Amicus]

Are emerald crabs reef safe?

 

[Kopitar]

I have 2 of them in my 75 gallon never had a problem

 

[Amicus]

I ask because I have a large colony of candy canes and one of my emerald crabs was crawling deep inside of it. Wasn't sure what it was up to.

 

[Daniel Fishy]

They are really good at removing unwanted algae deep inside corals. I never had a problem except the normal damage from there work inside new corals like glove pylops or zoas with unwanted algae in between.

 

[LaWoWee]

I had to get rid of one because it would also climb in my birdsnest and pick at and eat the polyps.

 

[MacDracor]

I would suggest a search on this site for "emerald crab" and count the number who've never had a problem (I have seen three people say that) and then count those who growled and struggled to catch their little coral killer (happened to me and I've lost count how many others). Essentially, it's like Russian roulette, except in this game, only one chamber is empty.
You may beat the odds and never have a problem. But I wouldn't bet on it. I've removed two for eating coral, and there was no shortage of other food available.

 

[Reeffanman]

I have one in my sump he does fine there

 

[Sniperhank]

Crabs in general are opportunistic feeders, if given the opportunity it'll occur. I have 3 emeralds in my reef without problem, but I truely feel that due to my constant algae growth has kept them so fat that there hasn't been a chance to think about munching on anything else.

 

[Leedowlrods]

I'm an emerald fan, I thought I had a problem when I seem him in a half devoured torch coral,
It turns out the coral had a disease and good old crabby was cleaning up the messy dead bits.
Ps, I've got two

 

[jmay33]

I honestly think it depends on which emerald crab you have. I've heard stories about them not bothering anything for a long time, then all of a sudden they eat corals.

 

[MacDracor]

One wouldn't think such a small invertebrate would have individuality, but they sure seem to! My first emerald ate spas within seconds of being introduced, and nibbled my torch hours later. The second was in there two weeks before I caught him eating coral. Others have reported weeks, even months of good behavior.
I love the look of crabs, I just don't trust them. And once they develop a taste for corals, I've not yet heard of them losing the taste for them.

 

[DanS180]

I have 1 in my 29g reef. Hasn't touched anything yet, also have 2 of them in my 90g reef, no problems there yet either.

 

[Amicus]

Thanks for all the advice. I think that, as usual it depends on the individual crabs. I have two, one green and one that is a reddish color, pretty cool. I have been monitoring it and I think it is just hanging out underneath the candy cane. I figure if I supply a steady feeding regimen then that should be OK.
However , I do think that my Tiger Pistol killed both of my peppermint shrimp. I always hear him clicking. He did pair up with my Blue Spotted Watchman though.

 

[melosu58]

They are really good at removing unwanted algae deep inside corals. I never had a problem except the normal damage from there work inside new corals like glove pylops or zoas with unwanted algae in between.

That would be my guess also. Most of them wont bother corals but there are exceptions esp. With crabs.