Looks like a large West African lungfish (Protopterus annectens) to me. It's definitely worth $150 at that size, but it definitely will not play well with others including those fishes that you mentioned as well as any other fish species including its own kind.
A South American lungfish (Lepidosiren paradoxa) or an Australian lungfish (Neoceratodus forsteri) would work with the SAL being the cheaper and more common of the two.