Strange Yellowing (picture included) What is it??

I was about to post that leaf width is genetic, not environmental, but a reread shows me that Jack addressed that point.
The thing I've not seen anyone address was from your post #2 ... about the droplet of sap with a bug in it. I do think the scars you've shown us are bug bites and not a nutrition issue. Even your "yellowed" plant does not show the telltales of Mg deficiency ... the color is too even. It could be that the pheno of that plant runs paler.
So I say insect damage. Keep an eye out for the pest in question ... it or its teeming brood might return! Have a management strategy handy in case it is a thrip or similar sap robber.
My only tiny suggestion (to amplify Jack's already excellent advice imo) would be to keep a dummy pot with your dry soil mix on hand. that way you can get a feel for just how wet or dry a growing pot is. cn

Alright. First thing I'm going to do tomorrow is check the pH of the soil. I'm kicking myself for not having done this while prepping the soil, also kicking myself for not adding perlite.

As for the pests; the cinnamon dusting seemed to work previously to rid my room of gnats, so I did that again. I have some organic insecticide if I need to go commando, but I'm trying not to use it as I've read that the product has negative affects on plants.

As for the abrasions on the leaves, I turned the fan down, it was set to high to keep the mold and bugs away, but not it's on low to keep my pants from scratching each other.

Some of the plants that I've noticed look yellow; I don't think it's the phenotype, they are not evenly colored. For example; on one of them the first few sets of leaves are a darker green and the newer growth is kind of a yellow that is slightly darker near the center of the leaves.

So tomorrow or the next day I will provide the results of the pH test. I am hoping I don't have to transplant these guys because I know that increases the risk of hermaphrodites and I already dealt with hermaphrodites during my previous grow.

ust the drips for your ph test and look into some drip clean, sounds like salt build up , u can get the build up from your ph to hi

Zuccotti, from what you describe about the new growth, it sounds normal. All of the new growth of my plants coming from the apical meristem is a brighter lime green than the rest. They'll darken up as they get used to the light. I just tried looking for some pics (I was really anal about taking pictures at the time!! And took lots of them) but sadly, the lions share are on the comp the cops got.
Get the soil pH. Thats the first thing you have to do. No sense trying anything until you are sure of that. Turning the fan down was probably a good thing, but remember, they survive wind in nature. A bit of abrasion to them is like scraping your knee. They will survive it, I can assure you.
Plants are individuals just like us. You are going to see slight genetic variations among them, and not everything you see is a problem. Just learn to recognize the overall health of the plants. As weird as it sounds, I can generally tell when something is wrong in the room just by the sense of well being I get (or the lack thereof) when I go in. You have to look at the plant in totality. It can have a bad leaf here and there and still be quite healthy. Bugs, they're a problem. Browning leaves, be concerned. Just keep your eyes on them, and they will tell you everything.

So today I popped into the garden and found that all of my plants seemed to be doing much better, less yellow coloration and a lot of healthy new growth. I am not sure exactly what made the difference (maybe it's in my head because I'm trying to worry less about the small things.) I have barely done much to them aside from spraying the leaves with seltzer water. I don't have pictures today becuase my camera battery is charging, but I will update with some photos soon.

I don't have a digital pH tester, but I followed the directions; added water to a few spoon fulls of soil mixed it and checked the results an hour later with my analog pH tester (the one you see in my moisture level status picture) and it says my soil pH is over 7.5. I really don't want to invest in a soil pH tester because I'm not sure how long I'm going to be growing in soil. Is this analog pH meter good enough to help me with my soil problems? And what should I do to fix this high pH? Should I remix the soil and transplant with added perlite and lime? I don't want to shock the plants, so if there is a way to lower the pH of the soil without transplanting that's what I want to do.

Oh, and about how long do you think it will be until I see the sex of my plants? They've been on 12/12 for about 8 days now, I think I am seeing tiny growths on some of the nodes, aside from the normal pair of green shoots that appear early on.

Sorry for all of the questions, I'm just very inquisitive and I want to get the best results from this. Thanks again for all the input, it's been VERY helpful!

Edit: I also watered them .6 gallons each just now.