As far as the best clown to try, IME a sebae or clarki clown is the most likely to host yer nem, you can also get an anemone crab instead of a clown, I have 3 nems, 1 RBTA w/ a tomato, a sebae w/ a crab, and a rock nem all alone, my 2 percs host everything but the nems lol, good luck