Starter not quite doubling every time?
I have a new whole wheat starter that I began 13 days ago, but was in the fridge for a few days after it was initially built up (bad advice, I know now :) ). I've had it at room temp for about 5 days now and it has pretty regularly doubled every 8 hours or so. One time I didn't feel like grinding more wheat to top off what I needed for a feeding late at night so I added bread flour and that time it more than doubled before peaking. I feed it once it has peaked. The last few feedings it has peaked before actually doubling. Am I doing something wrong? It's a stiffer 67% hydration type starter. I just don't want to kill it :).
It's like sourdough is a foreign language. Thanks so much!