Depends on how high you hang them above tank. Start them at. 20% and then slowly ramp them up over a couple of months. About 5-10% per week. Observe your corals. If they start to bleach turn the lights back down and wait longer before turning higher. If the start turning brown turn the lights up a little more.
it depends how deep is the tank
I mounted mine 10inches from the surface that's with my tank being 22inch deep
when I first got my leds I started them off in the lowest setting I consider the lowest setting 50%
than boost them up every other day a notch till corals responded
after I noticed corals closing I set back the whites little by little till they were happy 50%whites
now I keep the blues 100% whites 50% corals seem to like it and are happy so I'm happy
your corals will tell you what they like just watch how they respond