2 Questions(lighting, and watering)

I have a 150 watt HPS about 3-4' above plants, plants are about 6-11" tall and I want to know how low I can bring that light down? I also have a 75watt cfl (3') mounted vertically on the wall in between plants. How often should I water and how much to give them? They are in 8" pots. Also, how often should I give nutrients? Okay so I have a few more ?'s than I thought.
Also, I have them on 18/6 light cycle. PLease, your help will be deeply appreciated. This is my practice run since I am new to indoor growing.

Weed4Life:rasta:

you should be able to get it under 12 inches from top of plants,water plants when pots are dry,get another 8" bucket fill it with dirt and lift it this will give you your dry weight.give nuts every other watering,and don't try to push the plants with the fertlizer give them what they need.

Is very simple and cheap, but is working good. Plants are recovering real well from the nutr. burn.:stoned: