Hello @Bulbi ! You don't have to turning the plants. No matter if you turning them around your plant will receive the same amount of photons emitting from the lamp ! Nothing will change that. The sun didn't evolved and started moving for the favor of the plants but plants evolved in order to take advantage the movement of the sun and maximize the photosynthetic rate by using various mechanisms called tropism. One of theme is called positive phototropism ( its the phenomenon that leaves turning towards the sun). The only thing that you can achieve by this is a more uniform growth but the total weight of yield will be the same. Happy growing ! 👊