I'd say your tank should be at least 6mo established for a nem, and having said that and seeing you're real new here, most likely clowns first.
Also, check anemone facts up above to try to match proper clowns w/ right nem.
Make sure you have good light as well.
In a 29g I'd personally get a frog spawn or hammer for your clowns.
Most nems get pretty big, and tough to keep from intakes.