You need a very mature system for an anemone....like 8 months old at the least.Piggy is right,clowns don't need an anemone and you will need intense light to keep one.Nothing can foul a system faster than a melting anemone.You can add snails now if you are having algae they can feed on.Consider adding some nassarius to stir/scavenge the sand bed when you do add fish.