sounds all good to me seedking.You seem to have the right idea .
As far as the fertilizer goes i just use a good all round hydroponic 2 part feed,there are lots on the market it is usually personal preference.Get one lot for the grow cycle and one for the flower cycle.
You have a closet about the same as mine but i have a wall devideing one end to leave a 1.4 foot square chamber where i grow my seeds and cuttings under 130watt fluro on 16 hour days .This is the first time i have used fluroes for any type of growing.I use to use a 400 watt hps for this pupose and do the flowering under a 1000watt mh but i dont have the room any more.
You wont be disapointed with the 400watt hps it will be a lot better than flowering under just flouresent well worth the money...Well worth buying good seed to if you dont have good smoke around you can be asured the seeds will be just as bad as what you have been smokeing,you should be very happy with the northern lights....happy growing ,hope it works out well man....