brown tips?

my plant is about 2 weeks old and it is getting some brown tips in the bigger leaves! do i need to cut down the nutes in my bucket and during watering? im using fow farm grow big and the plant looks great its just the brown tips that bother me. when to i need to start cutting it back some the lower half gets good light also and the plant is albino rhino! thanks for all help! its only supposed to veg for about 4 weeks right?