I think I have crabs!

Hey 3reefers!

I walked by my tank a few minutes ago and caught something darting for cover on my live rock. This sucker was moving fast. Whatever it is, it likes hiding in a hole in my live rock. I've so far only been able to see his spider like brown legs which have horizontal light colored stripes going around them and part of what I believe is a circular shaped body. I didn't buy him so he must have been a hitchhiker. I think he is about the size of my thumb. Any idea on what it is or how I may lure him out for a better look. He's pretty shy.

 

Sally lightfoot crabs are very fast. I had one once, and it looked like you describe -- thin spidery legs poking out of a hole. As time went by, it came out more. Mine also liked to hang upside-down under rocks.
You could try to lure it out with a small piece of silverside or shrimp. But, it will probably grab it and go.

 

ha, its always fun to find somthing new u didnt know u had. well...unless its somthing bad, lol. i bet u could find him easier if u sneak over at night with a flashlight.

 

If you didnt buy it, the odds are that its something you dont want in there.

 

a glass cup with a piece of bait inside covered in clear plastic wrap with a slit in it held by a rubberband over the hole of the cup. place flat on bottom of tank with the cup filled with water of course. find a nice hidding place and wait.

 

I got a better look at it and it is definately a SallyLightfoot. So my understanding is that I do not want this in my tank, right?

 

I had sallys before and I loved them. Very interesting to watch and always working.