if the tank is mainly going to be for Elasmobranch's than the less lighting the better. during the day you will not see the shark. besides, have you seen what an adult bamboo shark looks like?
if the tank is not really designed around the Elasmobranch then pick the lighting to what else you want to keep.
our predator reef's lighting is based on the shrooms and zoas that we want to keep. so we only have NO bulbs on it. just remember the more light you have the less you will see the Elasmobranch.
G~
