Melt butter in large saucepan or Dutch oven on medium heat. Add onion, bell pepper and caraway seed; cook and stir 5 minutes or until tender. Add chicken stock, tomatoes, potatoes, paprika, sea salt and bay leaves. Bring to boil. Reduce heat to medium-low; simmer 20 minutes.
Stir in fish and shrimp. Simmer 5 minutes or just until shrimp are pink. Remove bay leaves before serving. Ladle into soup bowls.