For a little while I just thought I was crazy, but my Angelfish (and presumably all angels) make a noise. They do it a lot too. I can't find any information on its significance or how it happens or why, but it would be an equivalent noise to us clicking our tongues.
I hear them do it about every day now that I put them in a bigger tank and I sit closer to them. They're doing it right now actually. Anyone know why or how they do this?
I assume its a defensive or warning mechanism of some sort, produced by their pharyngeal teeth possibly?