Make the marinade. In a large plastic bowl combine soy sauce, water, brown sugar, Sriracha sauce, garlic, ginger, and sesame oil. Whisk thoroughly.
Marinate the fish. Add fillets to marinade (making sure each fillet is evenly coated) and refrigerate overnight.
Skewer the fillets on soaked wooden or bamboo skewers.
Preheat grill to 400 degrees, and treat grill surface with non-stick spray.
Place the kabobs on the barbecue grill, and cook 3 to 4 minutes on each side (or until done).