Yellow leaves

Hello, there are most likely multiple deficiencies, but not because they're not they're just because they're unavailable. Either you can try to ph your water much lower like 5 and attempt to get the coconut down more. Otherwise since its a photoperiod plant, you could set up a new coco pot and dig them up and transplant. They would likely recover given the right circumstances and environment. If it were a autoflower that would be much harder to get back on an even kiel in time.👍

You have an extremely alkaline substrate... try to transplant ASAP. It'll recover after that. If you leave in that pot, it'll take forever to correct pH and any imbalances to nutrients caused by crap coco. ( i feel your pain! ) it's whacky to be that high of a pH even with unprepared coco. The problem with unprepared coco is typicalyl Na+ content and/or what is bonded in the cation exchange sites (the stuff locked away from plants, unless equillibrium changes then it releases an overabundance of K+ as Ca and Mg ions have stronger affinities for the bonding sites). this is almost certainly pH related, as i've seen K-tox / Na-tox from crappy coco recently, lol. it'd be dark and sickly with twisted leaves and growing ugliy as hell.

Si el coco tiene ese PH lo mejor que puedes hacer es, no perder mas tiempo y poner otro con el coco bien preparado, mientras estes en esos valores de ph la planta no podra absorber ni nitrogeno, ni hierro, al no asimilar el hierro tambien provocará deficiencias de calcio y magnesio, aunque le rieges con cal max, esta condenada al fracaso, la unica solución que veo es trasplante a un nuevo sustrato, pero si tiene dos semanas, es mejor que empieces uno nuevo por que es lo va a tardar en recuperarse y cojer ritmo de crecimiento

You are getting a combination of calcium deficiency and sulfur deficiency with the yellowing of the new leaves . As a coco grower myself . It would be best to buff your coco with calmag and iron supplement at a lower ph around 6.2 for better nutrient uptake . Sulfur will get locked out at a higher ph level. I recently had a problem with my ph pen giving wrong readings causing me to lock out my sulfur uptake . Hope that help and good luck to you ✌️🏾

If it started off like this then it most likely will carry on like this. If its in the same substrate and the same feed as the other?I have a similar thing going on with my runtz, nothing I did but they look completely different! 🌱😊👍