i have KZ in my 4 lamp which are more or less the same thing as the ATIs only the day lights are 10k and 14k where as the ATI is 12k. anyways i have a 14k a fiji purple and 2 super blues and they are extremely powerful and the color is great.
corals do best with high PAR and a wide range in the spectrum, but remember different corals in nature are at different depths and the color that penetrates the deepest in nature is ble, which is why the water looks bluer the deeper the water gets and the clearer it is when it shallow. that being said the assumption that SPS
that are closer to the surface would benifit more from a wide range of like and i would say aim for about 15k-17k color in the system but some like it bluer then that