I have two viparspectre 450 LED lights in a 2x4x5 grow tent.. 18/6.. happy frog soil.. just fed them with 1/4 dose of fox farm big bloom after I saw this problem yesterday.. the lights are over two plants at 5 weeks old.. 28 inches above the plant canopy.. top leaf tips are curled down and a lot of the leaf is starting to turn brown.. the upper leafs of the plant are curled up like a canoe.. refer to the pic.. I am assuming it is light burn so I took one light away.. am I on a good track?