Wash the salmon fillets thoroughly and place in a pan.
Combine soy sauce, olive oil, garlic, ginger, and sugar in a large bowl and mix well.
Pour the marinade over the fillets.
Place in the refrigerator for around five hours.
Set your Z Grills to the Smoke setting and pre-heat for 15 minutes.
Place salmon on grill.
Smoke for 60 to 90 minutes, or until fish flakes nicely.
Serve with favorite seasoning.