What was found
CREW WITNESSED A HYD 1 LO QTY CREW AWARENESS ADVISORY APPEARED IN FLIGHT. FLUID QUANTITY ON HYDRAULIC SYSTEM NUMBER 1 INDICATED IN THE AMBER. DETERMINED NO MX ON STATION IN T89 SO CREW ELECTED TO RETURN TO AUS TO HAVE MX ACTION COMPLETED. CORR ACTION- MX DETERMINED SYSTEM 2 OVER SERVICED AND SYSTEM 1 LOW. MX TECH BALANCED THE SYSTEM AND SERVICED HYD SYSTEM AS REQUIRED. AIRCRAFT RELEASED