What is the deficiency on this Gorilla Cookies strain? How do I fix it?

Autos do have a short life span and I noticed my plants lower leaves did this when I saw nothing else wrong with them. I plucked the leaves and continued watching and checking runoff ppms and ph. I grew in coco so ph wasn't my issue I was worried about ppms. Always follow the 10-20% water runoff rule. And make sure they are not 300ppm or more above your input ppms or your over feeding. Or 200ppms or more "less" then your input ppms. Or your under feeding. Environment plays a role so Google a good vpd chart, I use pulse vpd chart. Make sire your in the correct zone for your current stage of growth! I see nothing wrong but lower leaves dying off due to short life span, although a runoff check will tell you if you're deficient or toxic and then we can go from there! Please consider me as the answer to the question so I have a chance to win grower of the month contest 🙏 please and thank you 😊