I've only been practicing KNF for a few months. As a chemist, I'm checking the pH of fermented plant solutions and Indigenous MicroOrganism solutions. We use rice instead of potatoes. Both pHs dive to around 4 and stay there. When diluted for the fields they pull the applied solution pH down to 4-4.5.
I've been trying to maintain both the FPS and IMO solutions arolund pH6.5 using dilute KOH, checking ~ every 12 hours, each time the pH is down below 4.5. I adjust it back up. Now looking for similar experience and finding nothing about pH checking in JADAM / KNF.
Any ideas anyone?  

Thanks for your comments.
There is very little mention of soil pH in my books.
We believe that explaining soil based on soil analysis and data on pH and EC will not be of much help to humans intuitively understanding soil. This is to make JADAM farming methods easy to use even in areas where scientific analysis cannot be done.

Potatoes boiled with JMS are used, and the pH of microbial culture is maintained at around 6.5. Frequent use of JMS will restore the crop to a suitable pH.