Day 15: PH is good. PPM good. Humidity problem during the day. Going to turn off the humidifier sooner so the light can reduce the air vapor before it turns off. Not very happy with where the plant is at this point, but it's because I screwed up the start, which is just going to delay me a bit but it's all good.
Day 18: Full reservoir change. Increased PPM to 600 because I think the roots are willing to eat it up.
Day 20: PPM dropped 60 and the plant drank a half gallon. All new growth is super green and healthy. In the next few days I'll probably pluck those ugly first leaves off.