Crab on my Acropora Tenuis

[Billyreef-ita]

Hi everybody,
I bought an Acropora tenuis and just discovered a crab happily living within the frags of the coral. It seems cleaning and eating stuff on the coral. I thought they are sort symbionts that’s why I left it on the coral.
This morning I noticed some little scratches on the coral, I wonder if it was the crab.
Should I leave it there or move the crab elsewhere?
Thanks

 

[elysics]

There a good ones and bad ones, can you take a picture?

 

[CoralCrafted]

I bring in a lot of acros, and 9/10 have these crabs, I prefer the when in doubt toss it out. I do notice the “scratching” and ever since I saw it the first time I just pick em off and in the sump they go!

 

[homer1475]

More then likely if it's real tiny, it's an acro crab(trapezia) and 100% beneficial to the coral.

 

[djf91]

Probly Tetralia species. Those seem to prefer Acropora.

 

[Billyreef-ita]

There a good ones and bad ones, can you take a picture?

Sure, I’m trying, not easy now he’s hidden, I’m waiting for him to pup up

 

[Billyreef-ita]

It is like if the crab knew we were talking about him , now I can’t find him anymore.
Is it possible at a certain point they leave the coral and move elsewhere?

 

[Billyreef-ita]

It is like if the crab knew we were talking about him , now I can’t find him anymore.
Is it possible at a certain point they leave the coral and move elsewhere?

Or maybe leaving the coral as it is not healthy anymore? In fact it seems to me the acropora is not doing very well lately

 

[elysics]

Is it smooth and does it have a creamy color with a dark bar across its eyes? Or white with red polka dots? Those are the most common good ones.

Bad ones being dark green/brown with sky-blue eyes and a fuzzy rather than smooth body

 

[Billyreef-ita]

It seems more of the good type, but now it seems gone….

 

[Billyreef-ita]

 

[Billyreef-ita]

Here it is….it moved on a milka from acropora tenuis…
Suddenly the milka polips retracted.
What do I do? Put the guy in the sump?

 

[MikeW9788]

Here it is….it moved on a milka from acropora tenuis…
Suddenly the milka polips retracted.
What do I do? Put the guy in the sump?

I hate to say it but that looks like a bad one. Send him to the sump.

 

[elysics]

It is a bad one yeah. Now and then they eat polyps. If your corals grow fast and aren't tiny frags you could leave it in there, especially a milka will probably do just fine. Or take it out and have a sump pet

 

[The Opinionated Reefer]

The blue eye'd hairy ones are bad. Also if your putting those indo colonies into your tank and and not dipping etc then you probably have AEFW now also. The fact the crabs are surviving means you have not dipped well enough.

 

[Billyreef-ita]

thank you all, so everybody agree this is the bad one, sump is waiting for him...
As for the dip, you are right, I did it very lightly because I tough the crab would be a good one

 

[Billyreef-ita]

thank you all, so everybody agree this is the bad one, sump is waiting for him...
As for the dip, you are right, I did it very lightly because I tough the crab would be a good one

one doubt: do you believe sump would be risky as well? as the crab would be reproducing?

 

[GlassMunky]

one doubt: do you believe sump would be risky as well? as the crab would be reproducing?

no

 

[Billyreef-ita]

no

Thanks! Crab is saved

 

[Sdot]

Thanks! Crab is saved

They eat corals... so it will prolly die in your sump.