CFs will be your best bet dude..The halogen lights are 100% useless..A cannabis plant will not grow with that spectrum..

In a 4x4ft square with a 7ft hieght i would advise using about 4-CFs considering each puts out 2300Lumen, however, this is only if it will be an enclosed grow box!!! The more light that escapes, the less light your plants will get. You must make sure it is flat white on the inside of the grow space to utilize the light efficiently as well..Proper ventilation should be equipped. You know, like a small fan and a few vents..

If you dont want them gettin big, then i suggest doing a strange indoor technique that ive tried a few times that seems to work out great for high yields! Keep your lights down real close to the plants, like an inch and a half to two inches away. Before the plants get too tall, place a layer of chicken wire fence over all of the pots/containers..Once the plants grow through it, TOP them. Then gently weave all the branches that come out of that through the chicken wire fence. Now, whats going to happen is the plants are going to continue to grow up at each branch tip. This makes it a little easier to utilize more space with less plants. Meaning you could cut down to like two plants and have 4 CF lights and still get the same amount of bud as you would from all 8 plants due to your growing space limitations..

Now if you really want to utilize your space and see some crazy shit, try topping each of the branch tips that begin to grow up after you weave them through the chicken wire fence...It can get rather crowded with buds so dont do it too much...