Place fish in a large ceramic dish and toss with 2 tablespoons lime juice and 1-teaspoon sea salt. Chill for 30 minutes to marinate.
Meanwhile, heat olive oil in a large saucepan over medium heat. Cook onion for 3 minutes or until softened.
Add capsicum, garlic and chilli, then cook, stirring occasionally, for a further 5 minutes or until capsicum is softened.
Stir in stock, tomatoes, coconut milk and coconut oil. Bring to the boil, and then reduce heat to medium and cook for 20-25 minutes until slightly reduced.
Add prawns, fish and marinating juices, then cook for a further 8-10 minutes until the seafood is just cooked. Stir in the remaining 2 tablespoons lime juice and season to taste. Serve with coriander and rice.