Man I would to know that process! I travel a lot to Germany and Denmark and trying to duplicate theirs but just not the same and I bet that it’s the flour!Wife has been on the sourdough kick for almost two years now. She’s got it figured out. Nothing better than fresh bread. She mills the grain for all the nutrients. The discard crackers and waffles are a nice bonus. You can store your starter in the fridge for weeks if needed without feeding. Pop it out let it come back to room temp and feed it up. Keep at it OP. You and your family don’t need all the preservatives in the store bought stuff. If you mill your own grains it’s truly bread of life. Store bought flour has been stripped of all the nutrients. They sell the good stuff to the livestock feed companies and sell us the crap with just the minimum amount of nutrients required to be put back by the fed. Started in the early 1900’s. People were literally starving to death and the fed had to step in. That’s why we have enriched flour at the stores.