Crab hitched a ride??

[reeffisher]

I got an emerald crab who was about an inch across from lag tip to leg tip. I had a bad bubble algae problem from a piece of live rock I recieved, the algae was starting to spread to other rocks in my tank so I did a little reasearch and found the emerald crab is about the best bubble algae eater. this prooved to be very true in a couple weeks he had cleaned all traces of bubble algae from the tank. a couple days ago I did some rock moving but didn't see him till a couple minutes ago, he has doubled in size. now if I can just get more bubble algae....