I can't believe these haven't sold yet. It's a great price, and South American Lungfish (SALs) are the coolest fish! I have three of them. They get along with most anything. They let me pet them and pick them up, and they eat out of my hand every day. They'll eat most anything (pellets, frozen shrimp, earthworms) and they can live for decades.
They do get about 3-4 feet long, but they don't need a particularly huge tank as they are very flexible and breathe mostly from the surface (they will die if they can't get to the surface).
Interestingly, they're more closely related to a dog than they are to a trout! That's a fact.