The details here are intriguing. It's also a kind of classic differential equation problem. I.e. take a desert lake fed by a small stream carrying dissolved m

The details here are intriguing. It's also a kind of classic differential equation problem. I.e. take a desert lake fed by a small stream carrying dissolved minerals, which loses half its water by evaporation (removing no mineral) and half by an outflowing stream - what's the concentration of minerals in the lake relative to the feeder streams? First, how long should you wait before adding fresh bones, vegetables, etc to the soup before serving it, if it's always simmering at 200F (94C)? Second, what percentage of the soup is consumed per day? Taking one bowl out a 100-bowl pot of soup per day is vastly different from serving 90 bowls per day, then restarting with only 10 bowls left in the 100-bowl pot. This allows asking the question, "what percentage of the food added a week ago is still in the pot". Also if you're adding bones I imagine the whole pot is strained from time to time to remove such solids.