I've been trying to find out as close as possible how much light I need to raise tomatoes in my GH. Stumbled upon an article that was about as basic as it can get. GH toms need 22 or more moles/day of light. Then I was able to find a way to calculate moles/day.
Foot-candles times .00071 (PAR factor for sunlight, HPS is .00047 and MH is .00054) times hours of light per day.
My lux meter reads 60,000 which translates into 5,584FC. That times the conversion factor gives me 4.26 moles. With 12 hours of sunlight I would get 51.12 moles/day.
