Heat olive oil in large pot. Dice onion, add to pot, sauté until soft.
Finely chop garlic and chilies.
Cut potatoes into 1/2 inch dice, and add to pot along with cumin, salt and pepper. Cook for another 5 minutes.
Add water and clam juice. Cover, Increase heat to medium high, and bring to a boil. Allow to boil for 10 minutes.
Add tomatoes, cod, scallops and lime. Cover and bring back to a boil. Cook for 10 minutes.