10 years ago i have used driveway lights kept at 5 inches away with small fan blowin on the bulb and top of the plant to rid the heat. got around qarter bag per plant.it will stretch jus a little , but work if your broke.thier 100 watts . 40 is week unless cfl , florecent lighting is cheap and affective with grow tubes.temps at 70 to 80, no sink water unless filtered water, air exchange.,nute lite every other watering after first two weex.remember....