Battling Aeration issues?

What you describe sounds like what I’m having. It may be an issue with nutes (the bigger gallons runoff ppm was on point, but the 1 gal ones were up by 200ppm, indicating buildup maybe). And I think my ph was a bit too high going in (high 6, I have changed to low 6. I will take a closer look at runoff ppm next time on those pots. it does help a lot to know from another person growing in peat. Thank you !!