i have no idea im seeing about 2 o's on the plant right now, and they just started to fill in, they have about 30 days left give or take so i think im reaching for the 1/4lb, Im using botonicare probloom, i notice alot of black crap on my roots i wash off every other day, and it settles at the bottom of my res, ppms remain the same so im not dropping out nutes, hmmm.. im gonna up the ppms to about 1700 tonight at lights on, see what happens when i wake up.