I have a 40gal reef with 4 Molly, 3 crab, and a variety of snail in my 1 yr old established tank. This guy (close up on right) and a few friends seem to have appeared from nowhere (snail hitchhiker I presume), but I haven't a clue what it actually is. I have never had (bought) anenome in this tank. He is about 3/8-1/2" tall atm.