What are false clowns? Do you mean Ocellaris? Otherwise, fish that aren't clownfish or damsel fish won't go in an anemone. If it is the Ocellaris clowns that we are talking about, give them time. If they don't host within a few weeks, tape a big picture of ocellaris clownfish hosting in a sebae anemone on the side of the tank and they will most likely go into the anemone.