You could get a couple of the lower wattage screw in type LED's or CFL's to do the job with a standard reflector hanging socket.., you don't need high wattage, for $40.00 or less on Amazon or eBay you would be set.
If using the 1500W, use just one and start high...use the back of your hand to judge distance, at seedling stage when they are tender, you don't want to feel any heat, but you also don't want them searching for light...Lower it till you can feel heat and then raise it up 8 inches, see how the plants react, if they look to be stretching, lower it a couple inches at a time until you find that sweet spot.
As far as nutes, start lite and slowly up them, keep a log of what you do so you know if you have to back off or up them, learn the signs the leaves tell you, the color, the position they present themselves ( droopy, flat, praying) are all signs of how happy the plants are...uplifted leaves are what you want to see with a true Green color, the stems should be a light green and fairly stiff, a slight breeze rustling them 24/7 is ideal, use the tent walls to bounce the air rather than hitting them directly.
Before you start your new run, clean the entire tent with a mild bleach/water solution, the current plants may have some of the diseases we discussed, we don't want any spores hanging around, and if you had any bugs, a product called Home Defense by Ortho is a great spray to keep the bugs away, it is safe to use indoors, pet/child friendly and keeps the creepy crawlers away, just follow the directions. I spray the inside and outside perimeter of my room and tent once a month...no bugs.
Another tip that mostly applies in the spring, summer, and fall is if you are working out in the yard, change your clothes and wash up before entering the grow area, drift from spraying weeds or ants catching a ride with you will cause all sorts of new problems.
