Hi, I am a 1st time hydro grower. I have a few questions I could not find anywhere. Help would be greatly appreciated please ... I am growing purple kush, 1. How much taller will my girls get once I switch them to flower 12/12 hr? Twice as tall as they are at end of veg? 2. My ppm was way to low when I started, got some plants with yellow fan leafs on bottom. I have raised the ppm to about 925 and they greened up except for the bottome leafs. Should I cut the yellow bottom leafs of that are not receiving more than 50% light? Is my ppm correct now about 925 and keep going up as I flower? How do I tell if ppm is to high? Some leafs have yellow tips, is that nutri. burn or still from not enough nutri earlier? 3. Should I turn off my fan that cools my plants while the light is off or does it matter? I have them in a small closet that I have to open to blow the fan in cause of space. Its dark, but when i flower since i will be home to open and fan when light comes on, should i just close closet with no fan so its complete pitch black? Thanks for all the help guys ... Ive been searching in the growers bible and everywhere online for these 3 questions. I really appreciate it.