You guys have been great so far for this new grower. You salvaged my plants by letting me realize I was way over watering and had the lights to close. After making those changes I gave my plants their very first VERY light first feeding. I used half the dose they recommended for a gallon of water for both FoxFarm "Big Bloom" and FoxFarm "Grow Big". I just got my bottle of Cal Mag that I'm waiting to use on my next watering. I'm attaching pictures of all my plants on day 21 (today), a picture with the effected plant that has a white circle around my area of question, and a picture of all of the products I have available to use throughout this grow process. Again it's day 21, it's grand daddy purp autoflower. Thanks for all of the advice so far and any feedback would be greatly appreciated. Lastly my humidity generally ranges 45 to 50% without and humidifier or dehumidifier..