It is very hard to keep them in a captive environment. Monterey Bay Aquarium is one of the few aquariums in the world that successfully keep tuna in display.
Musician's saying: "You can tune a piano, but you can't tuna fish."
In Polynesian mythology, Tuna is the god of eels who was sentenced to be executed (by the Upolo) after trying to rape Sina (who had grown him in a jar). He asked that his head be buried in the sand and from it, the first coconut grew. He was Hina's lover.