Partially Dry leaves in grow phase

Its a mag issue mate. & there's nothing natural about These plants are young.. its A typical late stage mag issue & needs 2 be addressed as quick as you can I suggest u get Epsom Salt. Make a foliar Spray. 150ppm added to as much water as you'd like. Just add that EC to it. Ph don't matter really..but if u going to also pour in sub (which would be silly not 2) ph for soil 6.5-6.8 Coco 5.5-5.8. Apply every wk in soil 500ml. And spray once a wk until she shows stigmata or until there's enough in your soil.. Don't leave it.. lack of mag causes serious issues to the plants growth capabilities and a whole host of other issues that will just compound Btw, if you do have ES at home..make sure its not fragrant salt or has aloe Vera It MUST be just plane Jane Epsom Salt. If you don't have any on hand. Get a calmag as most likely you may have a cal issue so ppl just use an all in 1 nutrient for both.. Just get a calmag not a + or 1 that has amino acids. Good luck