grow room Help

Alright, well this is my first thread for my first grow. I'm going to be buying a 4'x4'x6' grow tent from ebay. Along with a 400wMH (veg.) and a 400wHPS (flower). I plan on spliting the room with either panda flim or blackout curtains to form a veg and flower area.

My question is, how many plants will i be able to grow in this area with the 400w on each side? (Once i get going i will probably fill in with some T5's to help with coverage.)

Also, depending on how many plants i can grow comfortably with this much light, can someone please direct me in a DIY hydro system?

At first i was thinking about soil, but if i can run everything more efficiently and faster with the hydro why not choose
to use this method?

One more thing i would really appreciate some help on is my exhuast. (These tents you can check out on ebay just look up grow tents.) But they come with places for exhaust ducts, using the wattage i have what kind of system will i need? Please keep in mind i'm look for mostly do it yourself then upgrading .

The number of plants is really an open ended question. You should base your count on the lumen per sq ft. You can put 20 plants under those lights but what yield you will get will be the question. The min lumens per sq ft should be 2000. So if your 400w lights have a total lumens of 50,000 that could cover 25 sq ft of space and a small yield at that. Now take that same 50,000 lumens and use it in 16 sq ft or 4' x 4' area and you have 3125 lumens per sq ft and your yield increases per plant. I am running around 5000 lumens per sq ft. Size of pots you use will also be a factor. Without more info I would say about 6 plants will do well.

awsome man thanks for the responce. What i'm looking for is the fastest most efficient way to grow some goods buds. I'm new to this but have done some homework, can i get a greater overall yeild using 2" SoG having more smaller plants or doing less plants but increaseing the size of the pots to 4" or 6"?

The more room your roots have to grow the bigger your plants and yield will be. The strain of plant you grow is a factor as well.