The full fermentation cycle of the rye sourdough is 3 days, after which the sourdough is ready for use. Signs of ready-made sourdough: 1. The dough grows in volume 3-4 times after feeding, stands for some time at the highest point and then falls off. 2. 4-8 hours after feeding, the starter culture smells good. 3. The leaven floats in water and does not sink. If after 3 days your sourdough does not show signs of a ready-made sourdough, then it is not ready yet and you need to continue to lead it for several more days until these signs appear.
All you need:
a jar with a volume of 0.5 liters or a little more
lid for a jar with holes (holes can be drilled by yourself) 9 tbsp rye flour, perhaps more, if the time for ripening the sourdough is increased
drinking water at room temperature as required