@Frank the Dank
Turns out 50% on my fc3000 at 7inches was horrible, the bar style leds was not far enough away to spread out the par in the middle so.. the sides were getting 900 par while the middle was getting 400-600, went back to 100% at 16 inches
it would work good if the plant was growing into the led to dim it down but to save wattage on the power bill not so much.