If they are new, set them for 1/4 power for the first week, 1/2 the second, 3/4 the 3rd then full, or possibly leave them at 3/4, depending on the weather the corals like it or not. The color difference would be totally up to you. But you would be looking at more Blues than Whites, maybe 1/2 white and 3/4 blue once you've gotten it going for a few weeks.