A couple of weeks ago, I bought a pocillopra from SCFR. It'sa about 3 inches or so across. Since about the same time, i have been so busy with family obligations, I feed the tank but don;t really watch. So tonight, I had a chance to watch for a change. I fed the tank and was shocked to see the pocillapora had a hitchhiker - a small fish! It is about 3/4 inch long and has a yellow head with purple body. It stay inside the coral and does not leave. A bought a pavona at the same time and it has its own crab (looks like an emerald, fuzzy legs and all) but has darker claws. The crab stays with his coral all the time, too