growing white widow

I am starting my first grow, i have chosen white widow seeds for this. can someone please adivse on light cycles, ph values of water, nutrient levels to add, and at which times. when to change the light to bud. i have crafted a tall cupboard for my grow room, covered it with the dull side of tin foil (in order to stop sun spots, so i have been told). I have two fans, one bringing air in from the top, which is vented right down to the plants, and one at the top venting air out. i then have a 250w high pressure sodium bulb. the only problem i think i have is the depth of the cupboard is only about 40cm. is this too shallow for a grow. im only intending on growing 2-3 plants at one time. thanks alot for your time in this matter, i look forward to hearing from someone.

You are definately going to need a bigger box, if you want to use 250w HPS or you can use CFL-s or Envirolites which won't produce so much heat.

yea dude your going to need at least a foot and half to 2 feet for good grow space especially with a 250watt hps them bad boys can get warm.

In addition to what the other people said, you should also move your intake fan to the bottom of the grow cabinet, and get rid of the foil... Just paint the inside white.
It's much more reflective than foil. :)

Good luck with your widows, I vegged my last WW for about 2 weeks, and switched to 12/12 at that time... The plant was about 5 inches tall (not sure what that is in cm)...
By the time I harvested her, she was 2 feet tall... :D