I've got a crab in my nano reef that is steadily growing, and I'm worried he may become a pest. He came with the live rock and the first time I noticed him was about 3 months after I set up the tank. He was smaller than my pinky nail then, and now, about 10 months later, he is about 1 inch leg tip to leg tip. I haven't been able to take a picture yet (he's nocturnal) but I'll keep trying. Physically he looks very similar to an Emerald Mithrix crab, but his coloration is different. His legs are striped white/brown and his claws are brown at the tips fading to white. Any ideas?