goldfish types

Goldfish Care | Types | Best Tank

Goldfish in a bowl? No, that is not what you want to do. You don’t want to torture your fish.

In this guide you will learn everything you need to know about Goldfish. (Tank size, how to care, types, goldfish food, lifespan, tank mates, fun facts)

Goldfish Tank

An important thing to remember is that Goldfish produce a toxin called ammonia. This is very dangerous if you put them in a small tank, a large amount of this toxin can kill them, so it would be best if you can provide enough space for your goldfishes if you want them to leave longer.

goldfish oranda

All the goldfishes can grow very large, so you need to keep them in a tank that suits their size. Depending on the variety, single tail type can grow up to 12 inches and usually gets bigger than the fancy type goldfish. It’s true that if you keep them in the smaller tank and feed them less they can’t get that big, but this restriction is awful.

Some unwritten rule is 20 gallons for the first fish and 10 gallon for every additional fish. This is the rule that I follow for my goldfish tank. For the fancy ones you can get a smaller tank since they don’t need the same space as the single tail type.

Number of Goldfish

Tank size for Single type

Tank size for Fancy type

1 Goldfish

2 Goldgishes

3 Goldfishes

4 Goldfishes

5 Goldfishes

20 Gallons

30 Gallons

40 Gallons

50 Gallons

60 Gallons

15 Gallons 

25 Gallons

35 Gallons

40 Gallons

50 Gallons

They can survive as long as the water temperature ranges from 50-degrees to 76-degrees Fahrenheit. The most important thing that you need to remember is that they can grow very large, so you need to keep them in a tank that suits their size. In order to thrive, they will need a lot of room, so always consider a large tank. An important thing to remember is that Goldfish produce a toxin called ammonia. This is very dangerous if you put them in a small tank, large amount of this toxin can kill them.

Tank Decoration. Depending of the type of goldfish that you want to keep you must be careful with this part. I’m recommending you to go with small gravel sand because they want to disturb it all the time. About stones decoration you should avoid the ones with sharp forms. They can be very dangerous especially for telescope and bubble eye types.

We all want to have plants in the tank. Not only for the visual effect but plants provide more oxygen and are very good for controlling algae. But from the other side goldfish will eat almost all type of plants. Having plants will benefit your goldfishes in the way that they will have diversity food. On the other side you have to buy plants here and there to replenish the quantity that will be eaten buy your fishes.  

You will need a proper light to enjoy the beauty of the goldfishes. I’m using chip led light. Its more economical than T5.

Cycling Goldfish Tank

Goldfishes will release ammonia after they’re added in to the tank. For a few days after introduction in your tank, ammonium will rise and will be toxic to the fishes. That’s why in the beginning you need to change water more often. That’s how ammonium will be at low level until beneficial bacteria take control.

The best way is to use some live bacteria additives or to cultivate some beneficial bacteria in your aquarium before putting any fish in to the tank. That’s how you will detoxify ammonia.

goldfish type

Goldfish Filter

In order to have good quality water for your fishes you need a proper aquarium filter. The unwritten rule is to filter the whole aquarium water 10 times per hour. For example if you have 100 gallons aquarium you will need filter with flow rate 1000 gallons per hour. You can have a filter with higher flow without any problems, since all the modern filters have flow restrictor. I prefer canister filter because it’s more effective and its one of the easiest to clean. Check out my reviews for best aquarium filter for more info.

Water changes have a huge role in maintaining quality environment for your fishes. You can go with min 20% up to 70% water changes per week. The more the better. In the beginning you should aim for more than 30% water changes per week. Also you can do it two or three times per week with smaller water changes until you stabilise your tank with beneficial bacteria. I usually do 50% in the first 2 weeks and that 30% for the other 2 weeks. Next month 20% per week it’s enough. After some time you will get better and more experienced so you will not lose much time making water changes.

Do not add water too quickly when changing it. Adding water too quickly will shock the fish. Also you should add new water with almost the same temperature level as the existing one. The ideal water temperature for Fancy goldfish is between 65 and 72 degrees Fahrenheit. The single tail type can survive in cold water temperatures as long as the water temperature ranges from 50-degrees to 76-degrees Fahrenheit.

Goldfish Types

In general there are two types, Single tail (Slim Bodied) and Fancy (Egg Shaped) types.

 There are over a 100 species. Whilst the orange one is the most common, Goldfish come in dozens of breeds that vary in shape, colour, and size. The egg shape body is considered the fancy breeds. This includes the Fantail, Ryukin, Veiltail, Oranda, Telescope, and many more. Even though they come from Goldfish, they, in turn, have their own particularities.

Difference between Oranda and Lionhead is that Oranda has a dorsal fin, and Lionhead and most Ranchu don’t.

The Comet Goldfish is the most common one as it originates from Washington in the late 1800s. They, in turn, come in various colours but the most common one is the orange metallic. What’s very distinct about these is the fact that they have a large caudal fin. It measures half to three-quarter the size of its own body. The most unique ones are the Black Moor Goldfish, the Telescope Goldfish, the Celestial Goldfish, and Bubble Eye Goldfish.

Goldfish Food

They need their own type of food that contains less protein and more carbohydrates. The majority of the manufacturers have produced food with the specific dietary requirements, so you can pick up a tub of the generic fish food for Goldfishes. They usually come in form of flakes that float or pellets that sink at the bottom of the tank.

You have to remember that flakes will lose some of their nutritional value after the tub is open for a long period of time. As well as, they may swallow air when eating flakes off the surface of the water. That causes them digestion problem. 


They usually eat crustaceans, plants, and insects and will sometimes eat even smaller fish.

Over-feeding them can be very bad as they don’t have stomachs, so they don’t get “full up”. Thus, they will eat and eat as long as there is food available. Same as with other fishes the best way is to feed them more often small amounts of food. Especially in the beginning when your tank it’s not fully cycled and when you have small fishes that want to grow fast. Feeding those ones per day huge amount will pollute the water more than feeding often but small portions. The best thing you can do is feed them that much, that they can eat the food in one minute time. Do this 2 to 3 times per day

Goldfish Lifespan

If you take good care of them, the average lifespan of a pet goldfish is 5 to 10 years. In the wild, they have a life expectancy of 25 years! As long as you provide them room to grow, they will be able to live a long and happy life. Fancy goldfish have a much shorter lifespan as the average ranges from 5 to 10 years.

If you’ve ever experienced your fish passing away shortly after you have purchased it even if you did everything right, it isn’t your fault. Due to the fact that they are commonly found, they get shipped around from place to place and that causes them stress so it weakens their immune system. Therefore, their passing is inevitable.

According to BBC, the world’s oldest captive goldfish has died peacefully in his bowl, 43 years after he was won as a prize at a funfair

Goldfish Tank Mates

Mixing goldfishes? Is it a good idea to mix goldfish types in one aquarium? Well yes, but you shouldn’t mix single tail types with fancy ones. The reason is simple. The first ones are much faster swimmers than the round-body types and they will eat the food much faster. In some period they will become much bigger and will dominate the tank.

Goldfish are cold water fish and they need a steady temperature water. Thus, they are never compatible with any type of tropical fish as they require warm water temperatures. You have to remember that they produce ammonia which is dangerous for other fish. We recommend that you put them with Loaches because they are cold water lovers as well. Zebra Danios is also a preferred companion even if they are small. They are too fast for the hungry goldfish that mistake them for a snack. They will never have a chance to catch one of these.

Algae eating species should be avoided because they can cause injuries to the Goldfish. When no one is around, they will find the fish’s slime coat very tasty. This is very stressful for the fish. Nerite snails are very good tank mates that will help for algae control.

Goldfish Facts

  • They don’t have eyelids. Therefore, Goldfish live and sleep with their eyes open.
  • Yellow goldfishes were forbidden? Yes, in China, the yellow-coloured ones were forbidden to be kept by commoners, as the yellow represented an imperial colour. Those who had a Goldfish had to stick to the orange version. Nowadays, this is the most popular pet fish and they can be found at every pet store.
  • The most common fact known about them is that they have a short 5-seconds memory and they have very small brains. However, this species are capable of a lot of things. First of all, you can train them and they will retain that lesson for up to three months. They are a native of Prussian carp, native to eastern and south-eastern Asia.

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