Heat oil in large pot, then add onions and cook until transparent. Add garlic and spices, cook for another minute. Add celery and red pepper and cook until tender. Be careful not to burn garlic or it may ruin the flavor. Add the tomatoes and cook for about 20 minutes, stirring to prevent sticking. Add the Clamato juice and clam juice and fish and cook for 15 minutes, uncovered at full heat (do not add shrimp and muscles if pre-cookerd until last minute). Cover the pot, add salt if desired and cook for another 20 minutes on low heat. Stir often with a whisk to break up the fish and blend the flavors. When serving, add the chopped parsley. Excellent served with crusty bread. Frozen fish fillets work fine, no need to defrost them first, although they may require additional whisking.