At this point, I'm fairly convinced that Fishy is a she. I tried another mirror experiment in case the bow of the aquarium wasn't showing a true reflection. I shined a flashlight onto the back of the aquarium so that the entire back was acting as a mirror. Once again, Fishy looked at the reflection with curiosity, but no flaring at all. Fishy went straight up to the reflection and looked and looked, moved around a bit, and continued looking.
Well, boy or girl, Fishy is here to stay, but I am a little upset with the Pet Smart employees insisting it was a male. And I suppose as far as my son is concerned (since technically it's his fish, even though I'm more emotionally invested), it's a boy. I tried to say it might be a girl and he adamantly declared it wasn't, so I guess we'll continue to call it a boy but it's really a girl, unless, Fishy proves me otherwise.