Rye sourdough baguettes

Name: Rye sourdough baguettes
Prep time: 20 min
Cook time: 27 h 20 min
Total time: 27 h 40 min
Cuisine: European
Ingredients: 100 g filtered water; 100 g rye flour; 100 g Mother sourdough starter (see Tips); 360 g baker's flour, plus extra to dust; 40 g rye flour; 2 tsp salt; 220 g filtered water; ice cubes (approx. 10)