There is a very long and debated answer to this. I use 8 54 watt t5's from tek lighting and I keep anything I ant in there. Par is great corals are happy. 12 hrs atinics 8 hrs daylights. And I think there is never too much light. Remember the 10k 14k 15k 20k these bulbs start off whitish at 10k and bluer the larger the number. If you went with 20k you would have a pretty blue colored tank its personal pref. We can go on and on over lighting and I'll bet there are a few people here ready to speak there opinions for you. heres a link to light comparison.
CnidarianReef: Lamp Tests