some rough guidlines for light to go by are 50 Watts/Sq.ft. and 7000lumens/sq.ft. That is a good standard for indoor I hear. you can always do more light & you can certainly pull it off with less but those #'s are a good target. I would also say the Lumens/sq.ft is more important than the wattage/sq.ft. You could use bad lights & exceed the 50 Watts per sqare foot by a good bit and still fall short of your 7000 lumens/sp.ft. Now the lumens are a measure of light & that's what your plants need, they could really care less about what your power bill runs. & one last thing to consider is light spectrum. You could buy a totally wrong sort of light & get a ton of lumens but if all the lumens are being used up in the wrong spectrum then they are wasted. If you bought a light that was all green then you could get lumens from that & it wouldn't do the plant a bit of good. That's why growers use lights like HPS & MH. Metal halide has plenty of lumens spent in blue spectrum which helps veg & HPS has more red/orange & is better for flower.
As for floro's since it sounds like that's what you'll be using you should look into how many lumens you are getting and check out what spectrum or color temp they are. As for the tubes you can use the growlight tubes, but I've heard you can get effects just as well from using cool-white (more blue) & warm-white(more red/orange) bulbs & save money. But I can't speak from experience there. maybe someone else can.
& if I have any of my facts wrong plz correct me.
