1) Cut the fish into small pieces, no larger than 1/2 " cubes.
2) Salt the fish, then cover with the lime juice in a non-reactive (glass) container with a lid. Cover and set aside for 15 minutes while you prepare the vegetables.
3) Gently stir diced jalapeño, onion, cucumber, oranges, tomatoes, avocado and chopped cilantro together in a bowl. Once the fish is "cooked" (the fish will be opaque on at least the outer ridges), discard 1/2 of the lime juice from the fish mixture and pour vegetable mixture over fish and toss together. Serve immediately and enjoy!