Extreme Overnight Clawing - NO BUGS

[Purple_Drank604]

I had that problem when I ran a tier system and mine I figured it was the cold temp didnt have a chance to read upon other responses. But all my plants on the top tier clawed just like that but my bottom tier was fine had my ac pipes going down the middle so my micro climate was cold on the top and higher humidity hopefully this helps. Good luck and wish a happy grow for ya