I have no scientific backing on this, only observation from my first grow. When starting the seeds, they were on an 18-6. I took a group of clones (only one survived) and put it under 23-1 when I switched the main plants to flower. That bastard is growing twice as fast as the originals, although conditions are slightly different that may contribute to that. So, fwiw 23-1 is working well for me, but could be a variety of different reasons.