Bev, we had one of those evil crabs... had to "rock" it to sleep ourselves. Aren't they a pain to have in your tank??

Yeah, rocking the last one was very hard for me to do. Cried like a baby after it was done :cry:

But having them in a tank is even worse. Still have one in our 42 gal that I haven't seen in a very long while. I tore down the 42 over the weekend to rearrange the rock and corals. Swished every rock in a bucket of outgoing changewater to see if I could find the crab (and to clean rock of detritus), but he didn't fall out no matter how hard I swished :confused:

Sure glad I found this one in our 7 gal, though. Can't imagine what kind of damage the little fellow would do in such a small reef. teevee's on his way up here tonight to get him for his sump. Yeahhhhh, teevee :exclaim:

There are some LFS that sell Mithrax (Emerald?) crabs. Why are they considered bad?

specifically, it's the emerald crabs they sell, who will eat pest algae, such as valonia (bubble algae). however many people have observed that mithrax crabs, if hungry, will eat corals and even fish. this being an unidentified species, i would not want him in my reef either (hence why he will be living in the sump).

teevee,

I have some very small mystery sand-dwelling things that might be a type of anemone that you can have while your here for the crab. They will probably be good in your sump too :smile:

Was at the lfs the other day and they had emerald crabs for sale. They were very green. The mithrax I have is brown with red eyes, similar but smaller than the one in these photos:

http://www.lostmymarblz.com/42gal-mithraxcrab.htm

Our 42 gal had an anthias disappear without a trace. When I went looking for the body of the anthias, I came across the crab that a few people IDed as a mithrax and told me that it was not reef safe. I managed to get the crab out of the 42, which took quite awhile and numerous cuss words, and put it in our 2.5 gal for observation. While in the 2.5 gal, the crab started munching on some star polyps after lights out, so he was outta there in a hurry :evil:

Don't know if the crab ate the fish, but it wouldn't surprise me if it did. The anthias is a fish that sleeps and hides deep in holes in the rock - a perfect set up for a predatory crab at work in the night :sad:

HTH.

How did you end up catching him Beverly?

Caught the crab in the 42 by using two people each with a flashlight, a long plastic cable tie to flush it out of the rock and into the open, and a pair of tweezers to pick it up.

I've got one of those crabs in my sump if anybody wants him, while we're on the topic of crabs.

des

if no one else wants him i can take him next time i'm up, he can join his counterpart in the fuge or maybe he can live in a baffle :razz: i'm turning into some kind of SPCA for unwanted crabs here.