Hi Janice! Whole wheat pastry flour could work in a pinch but not for an extended period of time as there isn't enough protein in pastry flour to promote significant growth in a starter.

Bread flour on the other hand would be a great choice as it has a higher protein content and could be used interchangeably with all purpose flour with a small adjustment. For each cup or 120g of bread flour used, add an extra teaspoon of water to your starter to account for bread flour's increased absorption. Happy baking!

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