Are you supposed to test runoff pH in coco coir, and if so, what should it be? I've been watering with 5.8 pH 1/2 strength nutrient solution once a day. I tested the runoff a couple days ago and it came out at 4! I flushed it until it came out at 6, and now I've been watering with 7.0 pH solution with the runoff at 5.0. That still seems dangerously low to me.