Hmmm....don't know much about feng shui...but I supposed any vibrant coloured fish would be good. However, I would suggest that since this is your first attempt at fish rearing, it would be wise to keep hardy fish first, as dead fish = bad karma (as mentioned by Kev ).

Anyway, flowerhorn is quite a hardy fish. But have you thought of having a community tank? ie having different kinds of compatible fish in one tank???

However, the most important thing to do for the moment is to understand the cycling of the tank and to do tonnes of research on the fish that you want to keep.

Oh, and one more thing, fish keeping requires you to commit your time to maintaining the tank and the health of your fish. So, don't just jump into fish keeping just because someone says it's good for feng shui. Most importantly is your interest in fish keeping. Best of luck in your venture! :P