I would not suggest going below 10,000K. As Bryce stated lower color temps and you run the risk of algae growth. With a FOWLR lighting isnt' as important as it is on a reef however nicer light will make your fish look better.
I would go with a 50/50 mix of daylight (10,000K-12,000K and Actinic) and actinic.
You can accomplish that with T5HO for a decent price.