85% to 300% in a day
I have a starter that is about 3 weeks old, my first one. It was started with water and whole wheat flour then transitioned to white AP. It stalled when first feed the AP then got active. I was feeding at 12 hour interval using a 1:1:1 ratio, it would grow to about 85% but would never double. At day 10 I made some bread that came out OK, one straight starter and one with added yeast. The starter only one was dense but tasted fine.
A couple more days still not doubling, but tried again and got another dense loaf. Got tired of feeding and put the starter in the frig after it was feed.
A couple more days I took some starter out of the frig and made more bread, again one straight starter and one with added yeast. The starter was feed before baking and behaved like before growing to about 85%.
I left some of the starter out and feed it and it did the same 85% thing but the next day when feed it not only doubled but tripled. I used some the next day to make a straight starter bread and got much better results. I am still feeding it and it continues to get nice activity.
I could not help but wonder if I might have contaminated the starter with the store bought yeast some how, so I took some out of the frig to see if I could reproduce the behavior. The starter began more sluggish then before but after the second feeding it was back to 85% then more than doubled after the third feeding. I did not use any yeast in the kitchen during the experiment but the first starter was covered close by. Looks like I just gave up too quickly, any thoughts?
I did not use this site for getting started but did use it later to calm my nerves, so I want to give a big thank you to all of the people that have asked many good starter questions and to all of the people that provided excellent answers and information.