I am using hp promix soiless substrate, pH is good at 6.2, i have 4 different cultivers going right now under 600watt MH in a 4x4x6' grow tent for veg. Purple kush, blue cookies, Bubba Kush and Chem dawg..but only the bluoe ookiesare having the issue..I will post some pics when I get home. I am...