Fish Soup with herbs

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[...]

200 g salmon fillets , cut into 2 x 2 cm pieces 200 g cod fish fillets or 200 g other white fish, cut into 2 x 2 cm pieces 4 medium potatoes , peeled and[...]