I have a copperbanded butterfly that started head shaking. It almost looks like a neurological tick. It is very recent - this afternoon.

He shares the tank with 2 Dwarf Lions, and a Percula. He has been in the tank with the lions for 5 or 6 weeks and the Percula for over a year. He seems to swim rather close to one of the Dwarf Lions. I added a tang this afternoon but I think he may have been shaking his head before I added the tang.

The tank came with a hair algae issue that is yet unresolved and has just recently had an outbreak of cyno bacteria.

Any thoughts?