Well I've had my Arrow Crab for 2 weeks now and haven't seen much of him. He hid in one spot under a rock shelf in the back for about 3 days then moved and has been there since.
I did some research and it is possible that I may have purchased a decorator arrow crab which likes to hide all the time. Additionally they like to attach algae and small pieces of coral to themselves to grow as camouflage. I have noticed that his pointy carapace looks like it has algae on it but not the rest of him.
Anyone else have experience with a reclusive arrow crab, or arrow crabs in general?