Yeah; you can go 24/0 or 18/6 the only difference is; 18/6 they will show preflowers earlier than 12/12; if they even show preflowers on 12/12. Most strains will not show sex on 24/0. You can put them on 12/12 any time you want but the smaller they are the less your yield will be. I wait till they have alternating nodes. What's alternating nodes you say? It's when your nodes are opposite one another; instead of straight across from one another. When you see this your plant is mature and ready to flower. This strain i have now showed alternating nodes at 8'' and i put them on 12/12 and they have doubled in size in 18 days 12/12. Just remember; they will double or even triple in size when you hit 12/12.