Spontaneous combustion is my guess
First two or three weeks in flowering usually, stretch ends by the end of the third week.The stretch during flowering, I'm just curious how long does the plant "usually" stretch for?
They look lovely and healthy to me if they look like the second pic in your post #123, well done - good growing.They look alright babygro? The leaves you see that are curled in that one pic is from the side that I turned, that wasn't facing the light. Most of those leaves where bunched up in the corner. I think i'll only go with 2 plants for flowering next time, or that screen of green. These plants get too wide.