Does anyone have experience with arrow crabs. I'm planning on getting one, putting it in a little 5 gallon nano I have and feeding him bristle worms from my main tank . My question is.... how reef safe are they? Can I put him in my main tank temporarily at first, to kinda knock down the population, or will it threaten my fish and corals. Will it be easy to catch back out? Should I just stick to trapping them?