16 would be ok if you did sea of green, 1 per square foot, but go with less for just a growing plant and lots of space for sativa dominate plants. remember when you dealing with lumens that the amounts you want and get are to different things a 400 watt light will put out half its orignal lumens after 9 months say to a year, then your plants will be starving for light so i recomend going above the recomend lumens and replacing you lights often! dont for a good reflective surface, flat white paint. how many plants you will get in your space is going to be affect buy your typ of grow (ex sog, scrog) type of plant indica sativa, space and size of pots or hydro setup!
imagoober Reviewed by imagoober on . how much? I have 2 SON-T AGRO 400 ballasts with 400watt sodium bulbs and want to grow some weed. I have 3 plants under the 2 lights at the moment. However, they seem so bright i think i could have more, anyone have any suggestions? Rating: 5