150w HPS?!?

Well phenix tells me you can grow a couple plants with a

http://www.htgsupply.com/Product-FLORALUX-150w-HPS-Mini-Grow-Light.asp

And I only want to end up with 1-3 females, so could I use this? And if I do use this as opposed to a 400w, will I get less weed/have to wait longer?

Something else; about how much should I water them? I want to make sure everything's perfect.

150's are more then suitable for 2-3 plants if you are planning on keeping them small. you can most likely grow a 6 ft plant with one but would prob get the same amount of bud off a shorter, bushier plant. if your planning on keeping your grow small and compact, go with the 150...you wont be disappointed. if you think you need more then go with a 250 or 400. be sure you can control the heat, even my 150 throws off enough to heat up a small box if you dont have intake/exhaust fans. more wattage = more heat, be prepared for it.