hi there
i think you have bad ventilation, add some fan to push old dirty air away from tent out and open windows in tent to take fresh air :)
p.s. sorry for bad English :))
Hey mate!
Does not necessarily have to do with nute's. I guess its genetics, probably you have two different phenotypes, one with some more indica genes and one with more sativa.. but you don't have to worry!
Good luck 🍀 with your grow!
✌️