Just a bit of odd behavior I am wondering if anyone can advise on...Two of my Oscars began jaw locking. Their colors dramatically intensified, and their pupils dilated. They each began to jerk - not vibrate, but jerk. This went on for a few moments, then subsided. Breeding or fighting?

i've seen the same behavior with my o's. i think they were just testing there strengh or maybe establishing there dominance but as long as there's no actual damage to the fish i dont think there is anythinng to worry about.

That not odd behaviour, its perfectly normal for oscars

mine did the same thing about 4 months ago, now every once in a while they will go at it like that but not very often