I flipped the lights to 12/12. Tyreese already appeared to be stretching a little. The yellowing on the margins of the leaves has stopped with the addition of cal/mag. Here we go!
Thanks Tazard. One plant (Carol) is much shorter than the other and not stretching as much so I have to keep adding books under it to keep them at about the same distance from the light. The perils of growing different strains at the same time.
@Tazard, Thanks! I'm using a Viparspectra 600w LED. I'm only using 400w during veg. I'll turn on the red spectrum when I flip to flowering, bringing it up to the full 600w.