I think another one of the lower leaves is starting to yellow as well. It might have started a while ago and I just didn't notice. This is my 1st grow so i'm just going off the deficiency chart that I googled. I'll keep an eye out and see if any more start to yellow. Thanks for your advice.It doesn't look like N deficiency, but it's hard to tell under hps. The plant looks very healthy over all. I don't worry about one leaf, I look at overall health. So imho you don't really have anything to worry about right now. If a lot of leaves start looking unhealthy, then you can worry.
thank u.In my experience it's normal for leaves to slowly start to yellow from the bottom up during flowering. Maybe you could feed a touch more, but do not worry unless the whole plant starts to yellow. Good luck