Zuppa di Pesce alla Romana – Roman-Style Fish Soup


2 cloves garlic, chopped
pinch of red pepper flakes
1/3 cup olive oil
2 lb squid, cleaned and cut into 1/2-inch rings (about 1 lb when cleaned)
1 cup dry white wine
2 tomatoes, peeled, seeded, and chopped
2 tablespoons chopped fresh flat-leaf Italian parsley
pinch of salt
2 cups water
1 lb small hard-shell clams or cockles, soaked in cool water for 30 minutes and well scrubbed
1 1/2 lb assorted firm-fleshed fish filets such as whiting, monkfish, turbot, porgy bream, red snapper, and sea bass, cut into chunks