You are not talking about the fading leaves, no? I look forward to reading what others input here are. I am curious.

Mr. Super Obvious here but If the HPS made you happier, could it then be the lamp you are using now being the issue?

Are you heating the room aorund the tent? In my last grow I could not regulate the climate inside the tent well before I started stabilizing the climate in the room I had the tent in.