Question about leafs ( hydroponic )

Didn't mean to shield from wind, meant blown from wind. If you look at the second picture, looks like bottom leaf is leaning that direction as well as the ones you see clearly in middle nodes. That's why I questioned wind. Anyway, just wanted to change what I was saying to make sense.

Do you increase you fan speed when you turn up the lights to help with heat? Could be the plant trying to shield itself from excessive wind. If not, could be too much light, or picking up off reflection like others have said. Only time I've ever had one turn sideways was from too much air from fan. But I'm still new to this myself, so take what I say with a grain of salt lol. Best of luck! Happy Growing!

Weird, first thing that came to my mind was what ultraviolet already said. In German science language directly translated this is called erectile leaf position. But they would point upwards like leaves are praying in the direction of your grow light, its not just about the light more about conditions as a whole like Temperatur humidity plants are at peak performance on transpiring and light use when this happens. Germans like their plants to have an erection. Got this term from a lecture about greenhousescience btw :D But your leavs turn sideways and only one set does so or do you have a fan pointed at them or does the light come from the side? Reflection from black Plastik bag? Don’t think so plants would also freak out in growboxes with reflecting materials if this would be the case. Since they turned sideways reducing their surface exposed to the light this might be because of too much light? What kind of lights are you using man never saw this before

Maybe, the glossiness of the plastic underneath? The leaves contort like that toward light, so a glossy/mirror-like refelction might be tricking the leaves. The extra 15-20% might be enough to cause it but previous levels are not. bottom line is leaves contort like that because they are turning toward stronger light. Now, do you need more power or just giving more? 35-40 DLI is all you want. A plant can handle more than that by reducing pigmentation or it may take a long time to show some damage symptoms. Essentially, giving more either damages the plant or results in an adaptation to use less light in the leaves. There's no circumventing the limitation without extra CO2 and a well-controlled environment. if your light specs are accurate -- far from a given as most manufactures fib -- make use of a DLI table with hours of operation and see if that 15-20% extar is a good thing or detrimental Too much light is definitely a possibility. this could rule it out. Usually if light is too strong, it causes top-most leaves to show symptoms first. I think this is something tricking the leaves with a beam of reflected light or something.

Heliotropic is when leaves follow the sun, some plants can make their leaves go limp or switch directions when it's getting too much light and can no longer make use of the energy. I haven't seen it do that to just one set of leaves Weird huh.