sorry if this is a dumb question but im new to this as well and im doing a similar thing to you, 2 plants with 2 * 18w 2ft fluros soon to be a 250w HPS ill wait until they are a bit taller.
how do you use the moisture meter? i know you put it in the dirt but what numbers are you looking for? I suppose you just keep it in the green, is this correct?
I like your co2 idea, i might use it if thats ok
your ladies seem to be a little more advanced than mine.
i just transplated mine from soil into coco/perlite 50/50 mix so i need to relearn the watering thing again.
This is a small pic of my 2 ladies at 10 days. Just bagseed.
This is my first grow, sorry don't mean to hijack your thread.