I don't know this one. Was thinking Pelates (now Helotes) lineatus, Eastern Striped Grunter, but would need to count the stripes and see how wide they are. Any chance of a more side-on shot? Otherwise, leave it with me for now.
@AndrewG I'm thinking not eastern striped grunter, as the caudal fin in this sighting is strongly forked rather than truncate/slightly forked. It could be Australian Mado (Atypichthys strigatus), though the dorsal fin doesn't quite match up in this case. I also think the dorsal fin placement doesn't quite match up for Pelates sexlineatus either though. Both species have a light stripe as the apical stripe.