I just did a new round of water changes and noted some bubbles of the glass in some of the tanks.

The issue is best resolved with a DO meter.
I did note that the time it took to form new bubbles was about 15-30 minutes after the lights where on. The water change really sent the pearling into overdrive vs any night time water changes I've done.

I think many have noted this, even Amano has said things suggestive of this.
He likes to dose and do water changes in the morning, when the plants are able to use the nutrients the most and are actively growing.

Regards,
Tom Barr