Which deficiency?

later drop your normal ph for soil in range 6.3-6.4. Believe me it does magic.

Hi there It does look like a calcium deficiency but if your PH is way off there not going to absorb the feeds.. Adjust the PH and add CalMag if your not already, Try not to over water as there in big pots, Best of luck 🌱

I see calcium deficiency.. what’s causing it is another question

Pretty simple case of asking too much from the plants, switching to flower 4 weeks in 6 inches tall. Plant has 4 weeks of root development plant can only grow as big as roots allow. Being religious with "distance" (always keeping it x amount away) raising 1 inch, 1 inch is detrimental. The whole point of the stretch is to get the plant to its sweetspot for flower development. On the hottest days of summer runs around 1500-2000 umol, this is what nature can handle and so long as the leaf surface temperature is around 86 then photosynthesis will run optimally. Your plants look like they have been chasing high intensity light it so craves. This has given them long lanky internode spacing.

I think you answered your own question in the comment you made on your diary - if the pH was up at 7.3, neither calcium nor magnesium nor a whole lot of other nutes were able to be absorbed by your plant.... maintaining a good pH range is the number one most important thing you can do for your plants! Keep it between 6.0 and 6.5 and you'll be fine. The damaged leaves won't be repaired, btw... so don't expect that - but if you keep the pH in balance, there shouldn't be any further damage done... you might consider adding some Langbienite 0-0-22 to your routine - 1 tablespoon scattered on top of your soil once a month... Good luck!