To prepare Pineapple Salsa, combine pineapple, red and green peppers, cilantro, 1 tablespoon lime juice, red pepper flakes and lime peel in medium bowl.(Pineapple Salsa may be prepared 1 to 2 days ahead and refrigerated.).
Preheat broiler. Spray rack of broiler pan with cooking spray. Rinse mahi-mahi and pat dry with paper towels. Place mahi-mahi on rack. Combine remaining 1 tablespoon lime juice and olive oil; brush on mahi-mahi. Broil mahi-mahi, 4 inches from heat, 2 minutes. Turn and brush second side with olive oil mixture; sprinkle with white pepper. Continue to broil 2 minutes or until mahi-mahi flakes easily when tested with fork.
Serve with Pineapple Salsa.