Fish Soup with seafood

1 1/2 kilograms fish trimmings * 3 litres water * 1 x salt * 1 x peppercorns whole * 2 large onions chopped 2 each garlic cloves crushed 2 each leeks white[...]

4 tablespoons extra-virgin olive oil 2 pounds firm white fish fillet, such as red snapper or sea bream 1/2 pound scallops, muscle tabs removed, cut in half if[...]