are you talking about the little ones or the big ones? I have the giant Redeye tetras or Niger Tetras and they are vicious.
I didn't know there were more than one type (well except the "balloon" ones I saw at the store..)! Can't find anything on google about giant red eyed tetras so I don't know if they're the ones you have. My biggest female is a little less than 2" and I'm pretty sure she's fully grown because I've had her since January and my friend who gave them to me had her longer than that.