Well, that's different! You can keep and have what you want grow under your current lighting, but there is no garuntee that there isn't a little color change. Color change is more dependent on nutrients in the tank, stress, Color Temperature of bulbs, UV light present, etc. When I'm talking about your lighting, I'm talking about the life and death of the coral. FWIW, I know a few people that run 36" deep tanks filled with Acros that are powered by 6ft VHOs. Some of their acros are blue. Once again, I don't think what you have is a problem at all. If you want color, then I would focus what you have to the 20,000ºK spectrum with some decent actinic supplementation. The colors should be vivid and pop out as long as you don't have too much nutrients.