Is this your first marine tank? Exciting eh?!?!
Well, I think a Snowflake Eel would be the best option for you. Just make sure to have a tight fitting lid on your tank!
As for stocking suggestions, just stock with fish that are bigger than the eels mouth. Or, alternately, buy cheap fish (damsels, etc) until you figure out whether or not the eel has a taste for fresh fish. The eel should be fine with fish though if you keep him well fed. Forget about crabs or shrimps though. They will make a tasty snack. A few large hermits might survive. Tankmates? How about a fuzzy dwarf lion?
Best of luck with your new tank!