Hitchhiker crab found ! Is this reef safe?

[frizzayyyyreef]

Found it on a rock I was about to put in hiding in a anemone I have corals so I’m worried if it’s bad

 

[GillMeister]

It looks like you got lucky. That appears to be an Emerald Crab, and a female at that.

 

[G Santana]

That's a nice freebie

 

[neonreef3d]

males are known to eat some corals, and are aggressive, females are a safer bet for sure.

 

[vetteguy53081]

Mithrax and ones I do not trust- they eventually go after zoa

 

[frizzayyyyreef]

I had them before for bubbke algae they’re deff not reef they attacked my corals I just didn’t think he looked like a emerald because he was way faster but I’m not risking it

 

[frizzayyyyreef]

Mithrax and ones I do not trust- they eventually go after zoa

Which one is this?

 

[frizzayyyyreef]

I just got over a zoa spifer infestation I don’t wanna risk any corals dying I had trouble with these in the past if anyones in Nassua Long Island come get a freebie!

 

[vetteguy53081]

Which one is this?

Mithrax - emerald

 

[frizzayyyyreef]

Mithrax - emerald

Ty ! Off she goes

 

[GillMeister]

I've had several emerald crabs and haven't had any issues with them attacking corals. Knock on wood. Like any tank critter they can be completely unpredictable, but by and large these crabs are considered 'reef-safe'. Every algae grazer carries a certain amount of risk.
I've had problems with pencil urchins for example, but many people swear by them.

 

[frizzayyyyreef]

I've had several emerald crabs and haven't had any issues with them attacking corals. Knock on wood. Like any tank critter they can be completely unpredictable, but by and large these crabs are considered 'reef-safe'. Every algae grazer carries a certain amount of risk.
I've had problems with pencil urchins for example, but many people swear by them.

Had them in my last tank saw them actually eating lps.corals never again same with shrimp idc what anyone says

 

[G Santana]

I have two currently, all good so far.

 

[frizzayyyyreef]

When mine got bigger they became a very big problem easy to catch tho lol

 

[Karsyn]

It looks like you got lucky. That appears to be an Emerald Crab, and a female at that.

how can you tell if it is female? I'm wondering if mine is male or female.

 

[GillMeister]

how can you tell if it is female? I'm wondering if mine is male or female.

Males have one large pincer.

 

[blaxsun]

how can you tell if it is female? I'm wondering if mine is male or female.

Females also have a heart shape on their abdomen.

 

[Sink_or_Swim]

I've had several emerald crabs and haven't had any issues with them attacking corals. Knock on wood. Like any tank critter they can be completely unpredictable, but by and large these crabs are considered 'reef-safe'. Every algae grazer carries a certain amount of risk.
I've had problems with pencil urchins for example, but many people swear by them.

I have 2 very well behaved emerald crabs as well. Was afraid to get one because of some people's experience with them and corals, but I like them.