Ever fish keeper has heard of the Goldfish, those cute little gold and white fish that have been kept in captivity for centuries where even the actual date is unknown. Almost all kids love goldfish, little goldfish stuck in a small bowl with no filter, when i was younger i even liked this. But why did they always die? Was it something i did? Well its more like something i didn't do.
Minimum tank size: 30 gallons
Temperature: 60-73 but can survive as low as 2 degrees
Max size in aquarium: Fancy species 10-12" Comet species 8-12"
Well when i had my goldfish bowl, i never read any of this, nor did my mother who took the actual care of the goldfish. Almost 10 years after we gave up on the goldfish bowl, i got my first aquarium. Reading lots of books and doing lots of research, i have learned so much about goldfish.
#1: The basic rule of a goldfish is 1 inch of adult goldfish per 2 gallons of water. So if you chose a fancy species, you can fit 1 fully grown fancy goldfish in 24 gallons of water. This rule is basic and there are many different things about this rule.
#2: Goldfish are cold water fish, they thrive in water that doesn't go over 75 degrees Fahrenheit. During the summer of most families the temperature can reach 80 degrees and the goldfish wont like it. Unless the owner is willing to buy air-conditioning or constantly make ice-cubes, they will have to buy an aquarium chiller which don't come cheap. The prices go from 200 to thousands of american dollars.
#3: Goldfish are very heavy waste producers, they are what you may call dirty fish. They produce a lot more waste than the average tropical fish meaning they need very heavy filtration.
If you take all these points you will learn goldfish aren't cheap to take care of. Buying a 30 gallon tank with filtration that can control 60 gallons and buy an aquarium chiller or an air-conditioner, with all that money spent you could only get 2 goldfish for that tank. The comet goldfish goes for 12 cents each, so spending 24 cents on fish for a tank that costs you hundreds isn't always the thing people want to do.
The goldfish bowl is a topic i must talk about, almost all advanced fish-keepers everywhere say this is bad. I disagree, i say it is terrible, it is a torturing device in my eyes. With a bowl there is generally no filtration which means no oxygen coming in the tank, and no where near enough bacterial colonies to break down the harmful waste. The way to combat this is to do daily or twice daily 25-50% water changes in the bowl. But that doesn't mean problem solved, you still have to worry about size. Imagine a 12 inch fish in a 3 inch wide bowl. Simple math and common sense says no. Of course the fish wont grow to 12 inches in a tank that small, it will reach 2 1/2 inches and stop. This means its growth is stunted, a new problem with small tanks. Stunted growth doesn't mean it will stop growing and be a midget all its life without harming the fish. A stunted fish will die fast since it has lost the ability to grow. All fish tanks 10" or shorter can and will stunt the fishes growth.
Ok lets say you really want a goldfish and you have the money, i hereby beg you to buy one. What i said isn't trying to stop you from buying a goldfish, i'm trying to stop people who don't have the time or money that the goldfish needs. Ok now that you want a goldfish and have learned about there needs, you need to buy a tank. 55 gallons is great as i said on my other article. With 55 gallons, get a canister filter rated for 100+ gallons. If you live in hot areas without constant air-conditioning then you may need to buy an aquarium chiller to keep temperatures below 75 degrees. Buying fans can bring the tank temperature down a few degrees, if you rarely go over 75 degrees an aquarium fan is fine. Please also not that the colder the tank is, the more fish it can hold since it will have more oxygen for the fish and the beneficial bacteria. I will still recommend a chiller over fans to keep temperatures in the 60's so you can hold some more fish and your fish will thrive more. If you have a basement check your basements temperature, cold air is more dense than hot air so your basement will be the coldest part of the house, if your basement is cold enough then you may set up the tank there without a chiller, but keep some fans on the hood just in case. You can keep 4-5 fancy goldfish in this type of setup.
Please, if you are a goldfish keeper who have them in tanks below 30 gallons, please try to upgrade, if not look for a local pond at one of your parks or something and try to re-home your goldfish into the pond. Become aware and try to tell people that goldfish are not a beginner fish and should not be in the care of little kids in bowls. They require dedicated time and money for them to thrive.