I've always used 24/0 in the past and compared to grow logs that I've seen, my plants were doing just as well if not better than those on 18/6. I've never tried 18/6 though, so I really can't compare, but I've not seen any side by side pictures of one method being better than the other. Until then, I will continue 24/0 and 12/12, although I may give 18/6 a try in order to foliar spray my plants in the dark period, which is a no-no if you're running your lights 24/0.

Peace,
:rasta: