Quote Originally Posted by PhatJay
During veg/flower for best results you should aim for 2-4" in my experience. A lot will depend on how good the airflow and extraction is within your setup and what size bulbs you are using. If you see a lip forming on the edge of your leaves they are getting a little too warm. If you do try and keep your lights really close, be extra careful during first 2 weeks of flower when the plants are stretching, you will find yourself having to adjust your lights every 1 or 2 days.
Thanks for your input. I was trying to stay to the 2" rule but got a little worried with the leaf tip browning, which I then moved them to about 4", but seeing that is most likely a fert issue I've gone back to 2". Thanks mate.