I've, for the most part, always run 10,000K bulbs and get amazing growth. I recently upgraded to 250w bulbs and ballasts and the 10,000K were too yellow for me with 220w of VHO actinic and 2x54w T5 actinic. Keep in mind that this is on a 120g 4' tank. I think you are going to find those 6500K bulbs really yellow and the amount of actinics you are using isn't going to compensate for that yellow look. Also with that color temp you are going to be more prone to algae growth as well. I would strongly suggest rethinking that color temp bulb. 10,000K is pretty much the lowest most reef keepers go.