I'm growing some auto flower white widow plant under 300W LED. They are in the 4th week of flowering, and I just noticed some leaf issues when I checked on them today (i had been gone for the past two days). I'm having trouble figuring out what this could be based on googling, and wanted to share here with those who are more knowledgable than myself. I have attached a picture of the leaf here - It's turned almost entirely yellow on the outer edges of the leaf and then in the middle it has these rusty spots all over. Any idea what could be causing this? Of the 5 plants I have, only one is exhibiting this symptom. Thanks!