Many of us, have seen a goldfish or two in a bowl, purchased on a whim at a pet store.They’re “easy” pets, tiny little things who require only an occasional splash of food and the least amount of space — a circular glass sphere often small enough to fit on a shelf.
Or so we used to think
Attitudes toward the friendly little fish are changing. We shouldn’t let your goldfish live in a bowl.But why? As it turns out, fishbowls can kill fish.
It’s all about water quality, according to Paul R. Bowser, Ph.D., professor emeritus of aquatic animal medicine at Cornell University. “Think of it this way,” he tells The Dodo. “The goldfish is living in its own metabolic wastes.”
Fish poop a lot. And they excrete mostly ammonia, which bacteria then convert to nitrite, and which even more bacteria later convert to nitrate. It’s a natural process, but the mix of the ammonia and nitrite can reach toxic concentrations in a dirty fishbowl. And that can kill the fish.
“Remember, fish must do everything in the water where they live,” he said ”Eat, urinate, defecate, mate, breathe. They can’t escape their environment.”
Which is why filtration is so important. Bowser recommends a fully equipped aquarium with a bio-filter — commonly placed under the gravel or on the side — that avoids the toxic combination of ammonia and nitrite. Lots of space helps, too, and Lewbart says an aquarium should be no fewer than 29 gallons total for two or three small fish — and a single 3-ounce fish should have at least 10 gallons, if not much more.
With a standard fishbowl, filtration simply isn’t possible, and the fish will likely die.
“Unless the person performs very regular and frequent water changes, the concentrations of ammonia and nitrite can increase to toxic concentrations that could kill the fish,” Bowser says, noting that fish also do best at normal room temperature.
Of course, there’s also the question of whether goldfish in a bowl get sad or distressed living in such a small space.
“If the water quality is not optimal (e.g., high ammonia), I think they would be uncomfortable, and if the conditions were harsh enough, distressed,” Lewbart says. “I think they are definitely capable of being distressed/stressed, uncomfortable, and, at some level, could suffer.”
In the end, consider this, would you want to live our life in one bare room, with only enough space to go in circles? Us, neither. So splurge on that large, filtered aquarium and some lively decor, too.