I start hydroplex week 3 flower @ 1ml/gal, then week 5 i do 2.5ml/gal, Ive always used it so I dont know how much of a diff it makes, I use about 10-14 other products at the same time. aqua flakes A&B, root excelerator, drip clean, bud XL, Top Booster, b'cuzz bloom stim, mag-i-cal, protekt...