Six Line Wrasse behaviour

[Bob I]

I have this Six Line Wrasse who puts on a show as soon as he sees me. He stands on his head, flares his fins, and all sorts of interesting behaviour. He does this from quite a distance. At first I thought he was seeing himself as a reflection on the glass. This appears to be untrue, as I spend a lot of time in front of my computer less than six feet away from the tank. Anyone else notice this