Originally Posted by Hoppy
I'm not yet convinced that we need to be concerned about CRI for planted tank lights. If you don't consider that, the light can be a lot simpler, and less prone to having colored shadows in the tank.
Configuring these leds into a pendent style might take care of the expected colored shadows if they in fact do occur, but which hasn't been shown to occur conclusively. For example in this vid http://www.youtube.com/watch?v=4cRHcaPcY8w
starting at 5:53 the Acan rep is demonstrating their Prism light. You'll notice no colored shadows. Further into the vid the interviewer at 8:00 minutes mentions he see's no individual colors of light.
6500K leds have a good spectral distribution as is, but they have a blue gap. Adding cyan leds would fill in the gap and hopefully creating a high CRI at the same time.