G13 Indica Strain CFL Growing

Hey there here got one G13 indica strain in my closet with 3x 120 warm white cfls and going to add 3 more today, im already with light 12off 12 on to enter flower stage.
but as you can see on the pictures they are little damaged on the ends, not sure why, the lights are allways 2-3 inches away from the plant.
maybe anyone of you could tell me what could be the problem, its is not root bound or light burn.

Here is little update of the plant,
it have been on 12 on 12 off now for 18 days and its really bushy and lot of buds,
the plant is real healthy and mature, running on pure water and flushed
Here you go take a look at my pictures.