If you're going to try to pinch or supercrop, you at least need to figure out the basics. That would be like asking how to do a tail whip before even learning how to ride a bike.

Shoot for an average pH of 5.7, and don't let it go higher than 5.9 or lower than 5.4. As for the rest if you don't even know the basics of even what kind of hydro system you are using, its going to be hard to get any help. You should go to the Plant Problems forum and FILL OUT A FORM and try to get some pictures if you want some real help.