yes 2 feet is not a good start for marine and definately not with a top filter..... top filter are utterly useless for marine, suggest you going for hang on back filter such as eheim liberty 200................
And pls note that anemone require lots of light and is not a good start for newbie because they waste away easily, require regular feeding and often move about thus make them very easy target for power head :sick: ......... And when an anemone die, you would not want to know........ cos if you do experience that, you will feel like quiting this hobby immediately............
BTW pls note that, clown fish do not require anemone to survive