Some Plants Curling Under

I have a few strains growing right now, but these two are really giving me a fit. They are two different strains with similar symptoms, but I have the mother of the twin trunked one that isnt showing the same symptoms. The rest of the plants are fine as well.

1,000w HPS. Potting soil, R/O water, average temps are 80 or below, night temps 70-75. Rh around the mid 30's Ph 6.7

1st pic is Nightshift, the mother of the clone Im having issues with. Second pic is a Michiganja, which is growing next to it and as the others, is healthy. The third pic is the Nightshift clone that this thread is about. I just don't know what's wrong with it. Leaves very dark, stems red, it's leaf shoots are all curling, they look like green Cheetos lol. Fourth is a close up of the same. Fifth pic is Another view. Sixth pic is the AR-15. It's got the leaf curling, and it's getting worse, but is a much paler green overall, and the stems are red. The last pic is a closeup of the AR-15.

Bumpittybumpbump

What are you feeding them?

I have an assortment of nutes.

.......and again.

Anybody?

I see that you are using RO water, are you adding CalMag to supplement? How often do you water? What nute line-up are you using?
Love to help, but need more data.
On another note, you get down with the banjo? I noticed the case in the background of one of your pics.

I do supplement the R/O, but I've only had the system for less than a month so I'm very much a new-b when it comes to that. As far as nutes, I have an assortment to choose from, I only feed/water when the plant needs something, but on this one, I must have goofed. This thing is foxtailing and all the leaves are single blades. I think that others here on RIU were correct in diagnosing that I had to take them out of flower, re-veg, and now are in flowering, that can screw them up, but this nute issue still remains.