In a dry skillet cook cumin seed, uncovered, over medium-high heat for 1 to 2 minutes or until toasted, shaking the skillet frequently. Set cumin seed aside. Slice 1 carambola; cover and chill. Chop remaining carambola; set aside. Finely shred lime peel; set aside. Peel, section, and chop lime. In a bowl combine toasted cumin seed, chopped carambola, chopped lime, poblano pepper, cilantro, and 1/8 teaspoon of the salt; cover and chill.
Rinse fish fillets; pat dry. Sprinkle with remaining salt, ground red pepper, and lime peel.
In a covered grill arrange medium-hot coals around a drip pan. Test for medium heat above the pan. Place fish fillets on the grill rack over drip pan. Cover and grill for 8 to 12 minutes per 1-inch thickness or until fish just begins to flake when tested with a fork. Serve with carambola salsa; garnish with sliced carambola. Makes 4 servings.