That sounds good to me. If the shelves were any wider, you'd need two shop lights per shelf. I hope the back and sides of the shelf unit are open for good air circulation. Enjoy!!

Thanks starting threads "CharlieBoring". It sound good for me and DIY grow light is one of the best setup use for indoor cultivation.

Well, I set up my light system. Lessons learned - 5 shelves do not lead sufficient room for raising the lights, suggest 4 shelves. So far the only items I have under the lights are 2 goji berry bushes in pots until spring when I will plant them outside and potted geraniums. For these plants 12 hours of light are sufficient.

I have similar sized shelves to what you have, only 18" deep. In order to get the maximum amount of plants per shelf (seed starting) I run my trays/flats front to back. I have to have two fixtures per shelf in order to get decent coverage running them this way and I'm convinced if they had three it would be better because the plants on the outside edges of the flat are constantly trying to bend inward significantly. The flats just barely hang over the edge of the shelf, however due to the limited space between the front and back shelf support rods the lights cannot overhang so they miss some coverage on the outskirts ( I converted my shelving unit to chains instead of vertical rods and hung it but it's still the same problem). Two is the maximum number of fixtures I can squeeze in there per tier and that's just barely. I don't know the model # but I am using $17 T8 4' fixtures from Walmart.

Just some observations from a fellow newbie, I built mine in November. I also had a very narrow amount of space between the top light and the ceiling (we're talking maybe 4". So as an experiment and since I hate to see space go to waste I actually put a shelf above the top tier light and started several flats of veggies up there because it was very warm even though it received virtually no light. The seeds germinated wonderfully! Unfortunately because it's difficult to see up that high without a little step stool I didn't realize they had germinated so they were already very lanky when I caught it since it's so dark up top. Worked great as long as you check them daily, I must have missed a day.

Good luck with your setup!

I got this shelving at Home Depot but you have to get it online it is $89.99 now but you get free shipping.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=203800338&R=203800338#.UR1AF2eAN2Q