Place filets in a shallow dish or large zip-top bag.
In a small bowl, mix together the juice of 1 lime, oil, cilantro and garlic. Pour the sauce over the fish.
Store in the refrigerator for at least 30 minutes to allow the flavors to penetrate the fish.
Prepare the Salsa:
Peel and dice the mango and add it to the pineapple.
Chop the red pepper, tomatoes, jalapeño and green onions. Mix together.
Squeeze in juice from three limes.
Stir in minced cilantro and salt.
Allow the salsa to rest in the refrigerator for 30 minutes while grilling the fish.
Cook:
Preheat grill to medium-high. Lightly grease grill.
Remove the fish from the marinade and sprinkle with salt and pepper.
Place the fish on the grill and cook for approximately 5 minutes on both sides. Remove to a plate and tent with aluminum foil when the fish is opaque in the center.
Stir 1 cup of pineapple-mango salsa into the warm black rice.
Scoop ¾ cup rice onto 4 plates. Place grilled filets over the rice.