I have just put them on to 12 -12 .
they are looking healthy and not too much stretch, which is good. they are indica dominanat tho so they shouldn't stretch too much anyway. the topping has helped the canopy, lots of budsites, no pistils yet
@Tino14,
I had 3 No. 600 watt HPS above 5 plants in there.
the lights are worked off dimmable ballasts and work well. they are lumii digita ballasts, hope this helps.
@bigbadbillybob, la hidroponia es otro nivel pero la luz que usaste ha superado tus espectativas ? Busco renovar mi luz ya que solo son 250w que se aprovecha como se puede 😆