Uhm, I'm probably one of the worst to answer you!

Buuut, here I am..!

What kind of closet are you talking about? 7 feet are like 2 meters..! and that's how wide it is? how tall is it?

Any ways, If you have the money, get a HPS/MH converteble, if not, get some CFL's..!

Soil should be, somewhere beetween PH 6 - 7? I think so <---- (someone maybe correct me on that) Do NOT, I repeat, do NOT use outdoor soil, I did, and it sure as hell didn't work for me.. So, some potting soil, with the right PH, get that..!

Could you tell me how tall this closet is?