When you transplant them, mix perlite into the soil. The Jiffy pots look like they have some, but the black pots appear to have none.

Not recommended growing two plants in one pot. Roots and canopy will compete, at least one of 'em won't be pleased.

Let dry between waterings.

I'd raise the light a bit. They look too stressed, to subject them to full light and heat.

What's your water ph? What's the run-off ph?

6 day clones, looking that tall? Tallest clones I think I've ever seen, lol. Did you root them in a different room, then move them into the veg room 6 days ago?

Have you been plucking-off the undergrowth, or has it been dying off? Don't be a plucker. It keeps plants in a perpeptualy stressed state.

Good luck.