Mahi-Mahi
Fish
Doneness
Medium
54–57 °C129–135 °F
Warm pink center, firm.
Well done
60–63 °C140–145 °F
No pink, fully cooked through.
Tip
Fish is done when it flakes easily with a fork. Cook to safe temp or use the flake test — both work.
USDA guidance
USDA recommends a minimum internal temperature of 63 °C / 145 °F
Source