In the same pan over medium heat, soften the shallot and garlic in the remaining oil. Season with salt and pepper. Sprinkle with the flour and paprika and continue cooking for 1 minute. Slowly whisk in the clam juice and milk. Bring to a boil, stirring constantly, and simmer gently for 1 minute. Add the mussels. Cover and simmer for
3 minutes. Add the pasta, shrimp, scallops and fish and toss well. Cover and continue cooking until the fish and seafood are cooked, 3 to 5 minutes. Adjust the seasoning. Discard any mussels that did not open during cooking.