lol...why would plants NEED to get a flush upon entering flower? Only if you feed like an idiot and dump shit in uselessly, do you ever have to flush! Also, you link something for a potassium deficiency, so why are you saying he needs P and K? No wonder you need to flush...throwing in phosphorus on a plant lacking potassium..interesting lol. That's one main reason how you get lockouts! Learn what elements do, and learn what the plant needs and when, and you can avoid the useless practice of flushing...flushing is the equivalent of an eraser on a pencil! Not needed unless you keep fucking up your feeds!