Striped peacock eels, and tire tracks are true freshwater. However they are not technically eels but fish, that's close enough for me though cause they look cool. I have never kept a fire eel but they are in the same family. I currently have a tire track and he is awesome. He only tends to pick on other eels so I had to move my peacocks. Otherwise he doesn't bother anyone but at the same time he won't take others picking on him.