Slow cooker chicken stock

Wolfgang Puck says in his book that all great chefs tell that without a good stock, final dish wil suffer. Here's my version of chicken stock using a slow cooker. I added Japanese Kombu( Japanese seaweed for dashi) and Niboshi(dried fish for stock) for subtle taste.

3 pounds used chicken bones, after you ate roast chicken or Thanksgiving turkey.
1 medium carrot, trimmed, broken into 2 or 3 pieces by hands.
1 mdium celery stalk, trimmedn and cut into 2-inch slices.
1 medium onionm, peeled, trimmed, and halved.
4 cloves garlic, peeled and crushed by a kitchen knife.
3 cloves ginger, unpeeled.
3 bay leaves
2 sheets of Kombu
5 Niboshi (small dried sardines)
1. Spray 4-to 5 quart slow cooker with cooking spray. Place the chicken bones and all the ingredients in a cooker, pour cold water over to cover.
2. Cover and cook on low heat setting more than 10 hours. Strain through a strainer into a clean bowl and cool. Refrigerate, covered, for up to 3 day, discarding the hardened layer of fat when you use. Put the stock in small containers. Put them in the freezer for up to 3 months and reheat when you use.