How bad is this? (Emerald Crab)

[Johnson556]

I have three emerald crabs I in my 180G who have all settled on one mound. Recently I started restocking my tank with many acros after a pest infestation in September.

Well this week I noticed one particular crab has taken a liking to my garf bonsai. He’s always on this exact spot on the coral, which seems to be the only spot that accumulates algae from a tip I cut off and glued.

At first I thought he was just munching down on the algae but now I’m second guessing myself. Do I try and move him to another mound. Or just throw him in the sump. I can assure you, if I catch him on anything else, since all the other sticks cost 20x more than him, he will experience a pinch of death for sure.

 

[Aaron-A2]

I've never seen an emerald crab munch on coral. They will try and claw off algae/food stuffs and indirectly irritate the coral but I have never seen lasting issues with them.

 

[29bonsaireef]

Emerald crabs will harm Acros, not sure if they are eating them or just breaking them apart for fun, but they most definitely can, and will. I no longer keep them in my tanks for this reason.

 

[Whisperer]

I see my emerald often at the base of acros, the pick something there but it never skinned the acro.

 

[Mjrenz]

I used to keep some emerald crabs in my dt and saw them nipping at algae and then nip at a coral, it looked like they were just doing it without looking. After some tissue damage to the corals, I caught them all and they're now nipping at algae in my refugium

 

[Backreefing]

Well they eat alge and there claws have evolved into it , but they are stupid animals with a brain the size of a bread crum. If some acropora is brown or green and has tiny polyps that sway back and forth then stupid little crab will nip .
Imagine the coral in my picture with a emerald crab .

 

[Lapras]

keep an eye on it. i removed 3 female emeralds bc they were eating my stylos polyps! i also saw one trying to eat one of my acro polyps. needless to say, they're in the sump

 

[jda]

I have a dozen emerald crabs. They are always fine. I do keep them fed. You cannot expect them to just starve and die if they have nothing to eat, so you have to feed them. You would eat coral too if you got hungry enough.