Well... well... well... to harvest at max peek , you can make it as complicated as you want with plenty of brainstorming on the color of your trich’s and THC turning into CBN by oxydation with the oxygen in the air and the UVB light accelerating the process and all the others processes that are involved if you have a dissertation to do at your faculty ? OR you can just stop adding any nootz, particularly P-K, give it a good flush, as she really needs it by looking those dark green full of nutrients that their tips are burned ! And let it do her senescence, known as the fade ! As a total novice you should focus on your final quality before wanting to harvest tha kind of weed who’s gonna kill everyone... what’s the point to harvest at max peek if you harvest your plant fully green ang giving a harsh smoke ? See what I mean ? So, as Athos said , stay away from the technical stuff for the moment , just stop the nootz , flush it , and harvest only when it will be totally clear from any nutrients ! If you do it now , from my experience and what I can see on your pictures you should Masterize this strain without knowing what you’re really doing, but you will harvest the sweetest and the smoothest smoke you never had before ! Trust me ;)