[dawntwister]

The fact that the legs of the plants are very leggy, few leaves at bottom, shows that they are not getting enough light at the bottom. Things that would help compensate for that are making a reflector and dosing with Flourish Comprehensive or Calcium sulphate and Potassium sulphate.

What light do you have over the tank?

 

[dawntwister]

Oh!! I was wonder why the plants were so massive at the top.

How come you don't have the water to the top?

Perhaps dosing with Flourish Comrehensive or CSM + B would help get the growth you want in the back.