You only ever place your light at 100% on flower around a foot away to 18″ from top of canopy I try keep mine closer to a foot away.on veg you want to run your light around 60to 80% max on vege and 18 to 24 inches away from the top of canopy seedlings 25% to 60% and 24 inches to 30 inches away from the top of the canopy.This is what I have gone by for quite a while you will have to dial your own strain in to your numbers but if you stay with these numbers always start at the low end and gradually raise your light intensity and start at the high end away from your canopy too so you can slowly raise your light if need be that’s why I suggested that you started at the low number of light intensity at whatever stage your in now(example) say that you are in veg , turn your light to 60 %place it at around 20 inches away from the top of canopy and then you can dial it in to were you need to be) You should be fine no matter what strain you are growing if you can go by these numbers.I hope that this helps you out