Emerald Mithrax Crab and small fish?

[FamousGuy]

If i added a small goby to my tank, would an emerald crab attack it since they both hang out near the bottom and the goby would be small?

[Brianc_4]

Emerald crabs are considered "semi-aggresive". What the hell does that mean anyway? It means sometimes there is a problem and sometimes there is not.

So, you are left to go with what you do know. The more space in your tank for the goby to hide, as well as the crab to graze, the less likely of an adverse encounter. The emerald is also one of the few lovers of valonia(bubble algae), so if you have some in your tank the crab will be more preoccupied with an easier dinner rather than bothering a goby. The crab is a scavenger, not a hunter, but if space is cramped it will strike out. So take a look at your tank and see if you feel like you can afford the room to prevent a good ole fashion goby ass whoopin'

[FamousGuy]

haha, it's a 20tall so i'm not sure...it seems big, but thats compared to my five...the emerald crab is the only thing in there right now besides a couple hermits...hes strutting around like he's the top dog, and on top of that he's pretty grouchy. He always tries to claw me when i'm near the tank. I'm getting a clown/clowns once the tank is done cycling so i'll see how the crab reacts to them...

[The Unit]

it will be fine , i have had them w/ clowns, gobies, and other....i say go for it.......

[anthony812]

they will be fine, i had 3 in my 7 gallon Alife before, and now i have 8 in my 55 with clowns, goby, blenny, wrasses...they don't bother no body...they will just keep on eating your algae away...i love how hard they work in my tank, its been a pleasure to watch them..hahaha

[OscarBeast]

I had a neon goby go MIA when I had my emerald crab. He was the only suspect. However, the emerald was never convicted, because of lack of evidence.

[FamousGuy]

The clown was hanging out around the peak of the top rock in my tank tonight and i thought i saw the emerald crab lurking down below it but i wasn't sure...then i heard that "fish jumping at the top of the tank" sound. Turned on the lights, the crab was standing on the peak with his claws out and the clown was cowering in the corner...needless to say the emeralds been banished to my 5g

[Glenn]

There is a post on reef aquarium guide about an emerald crab eating a guys Flame Angel 2 days after he bought it. Along with that there are about 10 other posts reporting that these crabs eat fish and corals alike, so I wouldn't advise getting one. Although to be completely fare there are some people that have had them for a while with no problems. But then again I think that matrix crabs are oppertunistic feeders that will eat fish and/or corals if the situation presents itself. Just my $.02.