I remember seeing this animated short film on an awards show in the 1970s, '80s, or '90s. The details I remember are a man has a pet fish in a bowl. He takes the fish out of the bowl a little longer each day and it adapts to breathing air. He starts walking it out of the house on a leash and goes a bit further each day. One day they are on a bridge over water. The fish gets off the leash and either falls over the side or falls through a grate, into the water, and drowns. Other details I recall are that it was kind of simply drawn, and I don’t recall any speaking - it was shown with music playing.
