what am i doing wrong i have a lettuce tree

[superman]

well it has been a few months now since i started growing aquaponic lettuce. From the beginning the lettuce seemed to be growing oddly, but for me never growing lettuce before i just let it go and thought i would wait and see how it goes. Well it has been a few months and i can't figure out why my lettuce isn't hasn't like formed into what a lettuce head looks like instead i have a lettuce tree.

In the pictures the plant looks like it is dieing this is because i had to turn off the main lights because the lettuce was growing to high and burning itself.


Does anyone have any ideas what i am doing wrong?





thank you