Quick Question. Cal-mag or phosphorus?

Phosphorous, not cal/mag. Forget molybdemum, defeciencies of it is almost never.

Your plant looks healthy over all. A touch of leaf tip burn from excess nutrients in the soil or a one time hot feed maybe. Dude below my post is right. Molybdenum deficient plants can show purple colouring of leaves, but given the over all health of your plant, and the fact that a molybdenum deficiency is pretty uncommon, plus the fact that it looks like your growing some shitty auto flower plant, it's likely just the plant doing it's weirdo auto flower stuff. You are going to want to drop your pH though. 7 will work, but it's not in the ideal range for maximum nutrient availability. 6.2 pH is far better. I wouldn't do anything other than adjust your pH and monitor to see if it spreads or begins to show other problems. Right now, i don't see any big issue.

https://www.growweedeasy.com/cannabis-plant-problems/molybdenum-deficiency Think thats the one. Ph is essential in weed grow, around 7 is highway to disaster