I guess that’s the worst part I cannot confirm what caused it so I can’t learn from it I just calibrated ph pen, giving them water between 6.5 and 6.9 temps at 75 -77 lights on RH at 55% 65-70 lights out. At least in your case you can chalk it up to maybe deer pissed on the dirt. I am left scratching my head. 

I’d just chalker up to a weak seed.   And don’t feel to bad.  I’ve seen your grows, and there awesome.  Concentrate on the ones doing well.  I agree with chubby… move those to the corners.  I’m sure they’ll  give you a little something , but get the others  out front and center and ready for that flip!!   Good luck  !! 😊

I appreciate that Smiley, I wound up getting rid of the 3 and kept the 2 big ones. I’m not sure what it is but one of the two has yellowing leaves and the other is doing very well no yellowing nice spread with branches so I’m hopeful might just veg 10 weeks then flip and stack.