Bengali Cardinals mating?

[asylumdown]

Has anyone witnessed their mating behaviour before? Does one of them get two gross pinkish orbs that look like testicles popping out near the anus when they mate?

The pair that I have has been swimming in sync for the past hour, and one of them keeps doing this weird vibration thing with it's fins, and it's also suddenly got these weird pink orb things protruding out of it. They weren't there this morning, so I don't think it's a disease...