This is my first time growing indoors my space is 7ft tall 3.5ft deep and7ft wide. I can't decide on going dirt or a simple ebb and flow system. Any suggestions?
get a 1000 watt hps light and go dirt, the easiest way to go if its your first time. Once you got that handled, you should switch to other methods.
My advice is the same as darthhelmut, but I suggest going with 2 600-watt lights. 2 600-watters don't cost anymore to run than a 1k-er, and you'll get better coverage and more bud.
sometimes instead of buying multiple lights you can buy an intellidrive rail system. This system will drive around you garden from one plant to another very slowly. It can also pause at each end, you can programm it. It works very well and you can buy one for $150 which is a lot cheaper than a new light with the ballast not talking about the power consumption. check them out ehre http://www.elights.com/linrailligmo.html