When should you start your lights on a seed that just broke the surface of your growing medium? Right away? Im assuming you dont want the lights super close? Dont want them to get to lanky reaching for light at the same time. Using 2 unit farm UFS3000 lights.
So close to the light that you can feel the heat on the back of your hand is too close. Everything else is fair game.
Unless you have other plants too I think one light would be enough for seedlings.
Have 2 autos just sprouted in a 4x2 tent setup using 4 gallon pots. So they are already in their final pots didnt want to mess with transplants.