Kip,
Never seen that pic by Bennet, but that's pretty crazy color. I've asked myself the same question when i see different set ups and other pics that stand out with that amt of vibrancy. Although lighting is probably the primary contributing factor....other factors like bioload, type of fish food/coral food, Iodine, Mg supplementation also play a role. Just to keep up with my Ca/Alk demand outside of the Ca reactor i also add Kalk, CaCl2 and Reef Builder on different days of the week.