What Is the Appropriate Size for Your Goldfish Aquarium?

I just came across the video below and was blown away at how comprehensive it was (and the aquarium she uses is simply breathtaking!). But more than just the incredible scenery and beautifully colored goldfish circulating the tank, the author does a very good job in explaining how much space in an aquarium a goldfish needs to thrive.

Preferably, you'll want to put your first goldfish in an aquarium that is at least 20 gallons (80 liters according to the video). Any additional goldfish you add will require an extra 10 gallons (40 liters) per fish. This rule of thumb is generally good for fancy varieties (since they're slow swimmers and don't grow as large as common or comet goldfish). Single-tail goldfish varieties (generally commons or comets) are faster swimmers and grow pretty quickly, getting bigger than fancy goldfish. These goldfish will need 20 gallons per fish because of their large size. However, most aquarists keep such fish in ponds with kois, offering a larger environment than their homes will allow.

Of course, if you're just starting out, you can stock goldfish in a 10-gallon tank while they're still young and growing, but you'll need to upgrade that aquarium as they grow (even within a year). Personally, you're better off just saving the money and purchasing a large tank to begin with, rather than upgrading the tank every so often (coughing up more cash over time).

Better yet, build a pond! You'll still need to bring the fish indoors for winter months though (if the climate gets particularly cold in your area).

Note: NEVER keep your goldfish on a glass bowl. The author does a good job explaining why you shouldn't, including some very nicely done diagrams. But there are a number of reasons why you should never confine your goldfish in a bowl: the most important ones being that a) goldfish require a lot of space and a bowl will actually stunt growth (watch the video for some interesting theories as to how growth may be stunted) and b) goldfish excrete TONS of waste and that waste will quickly turn the water toxic, even killing your fish.

No matter how much goldfish food you feed your fish, you won't be able to keep goldfish successfully in a bowl. Either they die early or are absolutely miserable for the rest of their lives. Stay clear of bowls, and your goldfish will thank you ten times over by staying healthy and living long-lasting lives.

If you're considering owning goldfish (or even if you already have a few of your own), I highly recommend giving the above video a look.

For more in-depth guides on how to care for goldfish, visit Complete Goldfish Care, your one-stop goldfish care resource.

Happy fish keeping!