Season salmon fillets with lemon pepper, garlic powder, and salt.

Combine soy sauce, brown sugar, water, and vegetable oil until sugar is dissolved.

Place fish in a large resealable plastic bag, pour soy sauce mixture over fish, seal, and turn to coat.

Marinate for at least 2 hours.

Discard marinade. Wrap salmon in foil and bake at 425° for approx. 15 minutes.