There's not a lot of direct advice (that I've found) for how to water seedlings that are grown in their final container. Most of the grow vids online tend to talk frequency, rather than quanitity, and I cannot imagine that doing a full water with 20% runoff is a great idea for the girls at this stage.

For the first week, I moistened the soil up to about 4" out from the plant with a sprayer, careful not to get it "wet." Today (Day 9), I gave each plant roughly 1 quart of water, concentrating on the stalk and the perimeter at 3x the plant's current width as per Emilya's guidance here: https://www.420magazine.com/community/threads/the-proper-way-to-water-a-seedling-in-a-large-final-container.478973/

I'm waiting for "the plant's 3x diameter [to reach] the outside edges of the container" before giving it the first good soak.

• 6/4/22 — increased light strength from 50% to 100%. Distance is still 24".
• later that same day... I cranked it back down to roughly 60% or 6k LUX on the app I just downloaded. Tent was above 80° most of the day, which meant the fan was on high, blowing exhaust and dropping the overall humidity. Also moved the driver for the light outside the tent.
• Watered again on 6/7, giving both plants a half gallon of water at ph 6.5(ish). Tried to focus on center and the furthest permimeter. It looks like the next watering might be the first "real" one given the speed of growth. There was some runoff, which was surprising given how little water I gave them. Runoff ph was 6.4, ppm was 1893.