I agree with what I have seen... The plant can actually be taken through its entire life cycle with just one 23w CFL but you will have and extremely pathetic looking plant with maybe a 1/2 - 5 gram yield per plant. The more lights you use, the better your plants will look and yield. If you have a seedling that has only a few leaves on it, I think it would be a waste of light to have any more than 2 or 3 on a plant that small, but the more you can reasonably fit without burning your plant, the better you will be. Make your grow as big and high-powered as you want.