Red Emperors on the Great Barrier Reef are estimated to be 20-21 cm fork length at 1 year of age and 40cm at 3 years of age. Red emperors reach a maximum total length of at least 100 cm, possibly 116cm fork length and live to at least 10 years of age.
Red emperor is a type of seaperch. Despite its entrenched name, it is not an emperor (Lethrinus spp). Crimson seaperch (Lutjanus erythropterus) or saddletail seaperch (Lutjanus malabaricus) are sometimes incorrectly sold as red emperor