also if using the 1000 during veg your going to get a tremendous amount of brances and potential bud sites when u go to switch to 12/12.the more light the better.i usually start with a 2x4 flourescent setup with natural sunshine bulbs and then switch 2 a 600 mh.this time i have only used the flouros and they are half the size they should be and growth is a lot slower than when i use my 600.