It was going so well. I sterilized the jar and utensils, mixed in one cup
of warm water (chlorine free) with one cup of whole wheat flour and set
aside. After 24 hours the flour had settled, leaving dark water at the
top, but there were some bubbles.

Mixed, poured out one cup and mixed in 1/2 cup whole wheat flour and 1/2
cup warm water. In 12 hours the mixture had doubled, with bubbles about
1/8 of an inch across throughout, and was floating atop a layer of water.
The starter had a sour smell. Mixed, poured out one cup, mixed in 1/2 cup
whole wheat flour and 1/2 cup warm water, and set aside again.

Then nothing. After 12 hours there were no signs of bubbles. Mixed and
waited 12 hours more. Nothing. Waited another 24 hours. Nothing.

What happened?

- Kevin Cheek