Hello ! I saw different heigt and different wattage , I think it depend on the grower but for your bord around 12 inches for the lowest and 18 inches or more for the highest. What you need to know is that you need at least 50w by square feet so I think your 2 panels are good for one plant each if you'r not planning to fill the whole tent with the cannopy. I hope it will help you a bit 👍😁