EMERALD CRABS EAT CORAL

[MarsWulf5]

My Cynarina (button coral) was looking amazing. Then I noticed that it wasn't open and was closed a little lop sided and tight.

Today, it was still closed and I noticed my tiny emerald crab nipping at the Stony base of the coral. Then I noticed that it was receded - but not receded half eaten!!!

I was told that emerald crabs were reef safe - they were even advertised as reef safe - and I asked to be sure. I was told that he had one in his tank and that it never bothered coral.

I've had the crab only one month.
I feed this crab twice a day shrimp and krill and nori. He is very small, about 2/3rd of an inch. He managed to eat half of my large Cynarina which I just bought last week for $98.

I would not recommend getting one of these crabs if you plan to keep any coral. He looks cool - but I'm not letting him eat my coral.

My refugium isn't up yet - so, he's coming out of the tank now and going in a bucket until I can donate him to the LFS tomorrow.

This really stinks. I wouldn't believe anyone who says emerald crabs are reef safe about anything - seems like it should be pretty common knowledge. Maybe their crab in particular has been fine up to this point - but bottom line, Emerald crabs are not reef safe.

You can see all the damage in the pic on the top right of the coral. He actually picked apart the stony part of the coral and ate the flesh. It looks much worse from the top.

I hope this coral recovers somehow. Emerald crabs are awful!

 

[CWR24]

Suck they do!!

Many years ago I had one tear apart a very nice clam of mine. Spent so much time trying to get that little sucker out of the tank. Cool critter but NEVER again.

 

[Reef-junky]

Crabs are scavengers. I know they will eat fish as well if they can get a hold of them.

 

[MrDLHughesY]

Crabs are scavengers. I know they will eat fish as well if they can get a hold of them.

They are opportunists so yeah they may pic at corals if there’s not much for them to eat. I personally never had any problem with mine.

 

[motortrendz]

Not a fan of them. But on the flip side, how old is your tank? He could have been picking away at the dying coral. But either way I wouldnt chance it. he gotta go

 

[Leadfooted]

Mine not only got busted for eating the bubbles off my Sunkist Bounce, it was also tearing more bubbles off and shoving them up his sleeve / arm to eat later. I however have another still in the tank that's a team player and grooms the corals with care while grazing on algae. They're hit or miss

 

[MarsWulf5]

Yea, crab is banished. I won't be getting any crabs of any sort again. No crabs, no urchins, no shrimp other than cleaner shrimp - not worth the risk. Now that he is gone I realize that he was to blame for my Blasto receding. It wasnt too much flow, he was being nibbled away. Same with my Dunkin, he was nibbled. He's not closed, his polyp tentacles were eaten.

My Cynarina, Blast, and Dunkin are still alive - part eaten - but alive.

I'm glad I figured this out before any more damage was done.