Emerald Crab Eating Polyps

[pinhigh1886]

OK it is for sure now my emerald crab is eating coral! It has been picking at my birds nest and everyone I talked to said it was just picking for algae. I have been watching for a few days and tonight I could see him pulling polyps out and eating them on my birdsnest. I showed him off and when I came back a few hours later he was yanking on the red hairy acro I have and eating polyps again. I could see the polyps in its claw!! Anyone else seen this? I thought emeralds were reef safe. Might it be do to the fact that I have zero algae in the tank for him to eat? He seems to be just fine when I feed mysis shrimp. I tried catching him with my long tweezers. Failed! I got to get that little sucker!

[Tom@HaslettMI]

The only 100% reef safe crabs are the filter feeding porcelain crabs and acropora crabs (at least that I know of). The rest will eat anything... sure they may prefer algae but as you are seeing when the algae is gone they switch to other foods.

If its eating mysis you may be able to trap it using the the good old tilted-glass-jar-with-mysis-on-the-bottom trick.

Good luck with your crabbing,
Tom

[Danroth]

After the show on Sunday, I stopped by Preuss Pets & my dad pointed out the emerald crab to me. I pointed out to him that it was on a piece of coral and it was ripping the polyps out and feeding off them, and told him there's no way I'm putting one of those in my tank.

[jimsflies]

You need to get the tee shirt!

[110galreef]

I have an emerald that pretty much lives in my large sour apple BN. May have to keep a close eye on him. He doesn't seem to be doing any harm.

[jimsflies]

I haven't noticed them picking at corals much when I have kept them. If you have large enough colonies, I doubt they would cause major harm. But with small frags having an emerald picking at it would be a problem.

[pinhigh1886]

In a system with no algae they just get hungry and find alternatives. It may not be going after at first but it must of got a taste of one and liked it!! Still haven't caught him but I will.

[binford4000]

They got big pincher claws for a reason. Lol. Just get some wrasse's and they will eat the crab. Mine always make a good meal out of them.

[Reefman83]

yeah i normally take a small soda bottle a clear one and cut and reverse the top to it so its upside down in the bottle attach a string"fishing line" and bail you will catch him and if you have no sensitive livestock in refuge throw him in there no reason to punish him for being hungry or being curious

[Beryce20]

I had this same thing happen to me- just as everybody else said, once there's no food they switch to other eats---- mines gone now