I was thinking about the whole round bowl oxygen thing, and it begins to make sense. Compare a square fish tank to a bowl, both containing a gallon of water, then examine the top surface of the water which is exposed to outside air. The square tank obviously would have more surface area available for oxidation compared to the top of the spherical bowl. Otherwise, maybe the Italians are taking in a bit too much Chianti...(if I were a fish, I would want to swim in wine for sure
I tried to find a picture of a goldfish wearing glasses, but none were available. This is the closest I could find. She looks rather goldfishy.