Browning tips and lower leaves losing color

Northern lights 4 weeks 2 days flower I'm worried if it's nute burn or just normal. I have to make a decision on what I'm going to do. Feed nutes or just water. What should I do? Soil is currently moist still from prior feeding.

It’s nute burn from what I’m told but will say have done northern lights the last two grows and all have done this. So I don’t now. The bud still came out good so I didn’t worry about it. Haven’t seen too many grows indoor that doesn’t have some of it happening one way or another

The brown tips are telling you to back off the nutes a little..