Hi there I am currently 9 weeks 6 days into my first auto flower grow, and it is currently week 5 of flower (please see pictures). All was going so well, until I started to see some of the lower leaves show a deficiency in what must be a mobile nutrient as it is slowly working it's way up to foliage higher up. Since I've noticed this, the last two feeds I have really upped the nutrients; I'm using BioBizz Bio Bloom (5ml per 1l of water) and BioBizz Top-Max (3ml per 1l of water). I've been PH'ing the water to 6.5 as best I can with pH down etc, however I don't have a reliable or expensive soil PH tester. Only a cheap one off amazon, that is reading around 7... (no idea if it is right or not). Questions: Does anyone know what type of deficiency this is? I've looked at some charts, and I think it's a mix of a few deficiencies but I'm not 100% certain. Am I feeding this plant enough, given this deficiency? It's a single plant that has had LST. Any recommendations would be appreciated, and if I've missed of any important info please let me know and I'll respond asap!
Cut back P and K, add a bit more N. But yellowing is common at end of life. Flush and follow those instructions PH, 6.5 -- 7.0 is perfect. U are getting tip burns, dirt to hot, thats why I say flush.