Hi Lily, if you read through the comments below you'll see that you're not alone in experiencing the lull in rising around day 4, which can continue for several days. This lull seems to be related to a type of bacteria that produces carbon dioxide early in the process (giving the illusion of yeast activity), but actually contributes to a delay in the onset of wild yeast fermentation. Usually time and patience wins out and your starter will eventually begin to rise predictably, but if you'd like to try an alternative feeding routine that is meant to increase the acidity of your starter and help the wild yeast kick in, then you could try switching to feeding only once a day with whole wheat flour: saving 1/2 cup (4 ounces, 113g) of starter and feeding it 1/4 cup (2 ounces, 57g) water and 1/2 cup (2 ounces, 57g) whole wheat flour. Once your starter is rising predictably , switch back to the twice a day feedings with our unbleached All-Purpose flour, feeding once again with equal parts by weight of starter, flour and water. Once the starter is rising predictably with this feeding routine, then you should be good to start baking. Don't be surprised if you starter exhibits some sluggishness each time you switch up its feeding routine, as the organisms need time to adjust, but eventually your starter should start rising like a champ!

Barb

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