Hi, just checking. i have my 600w hps lights about 2 feet above the top of my 4 week old plants (from seeds). My research is giving me different opinions about the distance from the top of the plant. I have 13 young plants under 2 600w lights.
Also I was wondering when I had to start thinking about removing low down leaves, and topping or cropping. Should I just leave them alone for now or should I start thinking about maximizing the yield.