Hi Sanguine

Dazed asked me to have a look at your grow. From your latest pics, here is my take.
I agree with LoveHNLBLS (wow! great handle!..say it 10 times fast lol) that a flush might serve you well. Even with 5 days between feedings, they're going to hold some salts over the veg period, and that could well be the reason for the yellowing/atrophy in the leaves. They look like smallish pots, so a flush of maybe 2 gallons of a pH'd, 1/4 strength of your current nutes, should suffice
Another thing to consider- rather than 5 days(ish?) between feedings, consider reducing the amount you "water" to split the amount you use every 5 days, and give them half of the 5 day amount every 2-3 days. I have had plants that had the same lower leaf issues that you are showing, and the "fix" was water less, and more often. The more damaged leaves won't come back from it, but the newer growth will show the value in doing so, and within a few days

If you can post some closer shots of the leaves, it would help define it more clearly

Hope that helps, and feel free to PM me when you post pics, so I can pop in to look.
:karma Cloud: and :Sharing One: