Personally I would not be looking to add any more P and K Mg or S to this plants.
they look like they’ve been malnourished for the last month.
where’s your lovely green leaves gone?
the red leaved plant (tangerine) was/is a very problematic plant but in the same time very resistant (took all the cutting, topping, mites like a champ). tbh havent seen green leaves on her for over a month, because of mites, overwatering, low temps. i didnt thought the plant would make it as far as it got, she looked way worse. i came here asked for advice and implemented what other experienced folks told me. in result she got better and imo doing pretty great (cutted some lower stems 2 weeks ago and it got people, including me stoned, but the taste was very dreadful, bcus of neem oil) .
also i think she has different genetics, because clones taken from her revealed same coloration.
i agree theyre probably poorly fed for last month, but it was worse before.
as for the think fast plant, she was quite healthy throughout the veg cycle (a little too stretchy strain, mites got her as well, but didnt do as much damage) and was doing fine in early flowering. its been a week since she showed some top leaves yellowing, checked today and bottom 2 leaves started to yellow out, other than that i have no complaints, takes up water fine, smells really nice (probably best smelling plant ive ever grown, tangerine is also very good smelling).