5 X 5 = 25 square feet. My 600 watt bulb puts out 95,000 lumens. 95,000/25= 3,800 lumens per square foot. The 1000 watt bulb would average around 140,000 lumens. 140,000/25= 5600 lumens per square foot. You would like to be as close to 10,000 lumens per square foot as possible as this is what...