Please ID

Wiggie · 09/13/2018, 08:30 AM

7307.jpg
Are they reef safe?

Foundry · 09/13/2018, 09:03 AM

Nope.

These look like some branch of the Xanthid crab, a predatory hitch hiker. They can be disruptive to a reed system and munch on fish while they sleep.

We trapped and removed 2 from our tank after initial setup, they found they're way in on some LR no doubt.

Sugar Magnolia · 09/13/2018, 09:47 AM

Definitely not safe. If you have a sump put them in there.

mattgumaer · 09/13/2018, 09:56 AM

Not sure. Crabs are tough to ID a lot of the time. I think people tend to go by generalities, pointed claws=bad, more rounded=good, hairy=bad, etc.. I think the issue is that there are tons of different species of crabs and only a handful we routinely talk about in the hobby. So, it may not be possible to specifically ID them. If you have a sump, you could throw them in there. Otherwise, it's may be a question of risk tolerance.

I had a 90 gallon tank where I literally saw a crab waving around a still living fish by its tattered tail. I was able to remove the crab during a tank upgrade project.

If I were you, I'd either sump them or get rid of them. At a minimum, it's likely they're at least potentially bad actors and getting them out of a reef tank can prove to be a challenge.

Matt

09/13/2018, 08:30 AM	#1
Wiggie Registered Member Join Date: Mar 2011 Location: Florida Posts: 63	Please ID 7307.jpg Are they reef safe?

09/13/2018, 09:47 AM	#3
Sugar Magnolia Registered Member Join Date: Feb 2003 Location: Northern VA Posts: 17,691	Definitely not safe. If you have a sump put them in there. __________________ Adrienne The only thing to fear is fear itself....and spiders.

09/13/2018, 09:03 AM	#2
Foundry Registered Member Join Date: Nov 2016 Posts: 57	Nope. These look like some branch of the Xanthid crab, a predatory hitch hiker. They can be disruptive to a reed system and munch on fish while they sleep. We trapped and removed 2 from our tank after initial setup, they found they're way in on some LR no doubt.

09/13/2018, 09:56 AM	#4
mattgumaer Registered Member Join Date: Jun 2013 Posts: 561	Not sure. Crabs are tough to ID a lot of the time. I think people tend to go by generalities, pointed claws=bad, more rounded=good, hairy=bad, etc.. I think the issue is that there are tons of different species of crabs and only a handful we routinely talk about in the hobby. So, it may not be possible to specifically ID them. If you have a sump, you could throw them in there. Otherwise, it's may be a question of risk tolerance. I had a 90 gallon tank where I literally saw a crab waving around a still living fish by its tattered tail. I was able to remove the crab during a tank upgrade project. If I were you, I'd either sump them or get rid of them. At a minimum, it's likely they're at least potentially bad actors and getting them out of a reef tank can prove to be a challenge. Matt