GrowCNanswered grow question 3 years ago Do not pay attention to the artificial "equivalent" number that many inexpensive lights advertise. Look at the actual wattage consumed by the fixture. For a white LED I want a light capable of providing 30 watts per square foot minimum but 35 watts per foot is better. So, in your case 480-560 watts. And, I like a light or multiple fixtures to spread the light out. I do not like a super bright small light in the center as it tends to create a hot spot in the middle with darker corners while a physically larger light or multiple fixtures can spread the light more evenly.