Found crabs in my finger algae

[MEhart]

I discovered 2 crabs in a liveaquaria green finger algae purchase. I am very new to reef aquariums so any help would be appreciated identifying them as I am fearful of anything that might be damaging to corals, etc. (I emailed liveaquaria with photos but they were no help).

 

[cliffclaven]

I discovered 2 crabs in a liveaquaria green finger algae purchase. I am very new to reef aquariums so any help would be appreciated identifying them as I am fearful of anything that might be damaging to corals, etc. (I emailed liveaquaria with photos but they were no help).

Not 100% here but Kinda looks like a fiddler or maybe an emerald crab to me, either one should be fine for coral but any crab can "nip" at corals like zoas

 

[KJ]

Look like a Mithrax Crab. Put him in the sump

 

[ThunderGoose]

I've had a wide variety of crabs show up in my tank. The vast majority have stayed small and never caused a problem.

The two red mithrax crabs, on the other hand... they're now sump monsters.