How many goldfish you can put in a tank?
Goldfish is a very common fish among all aquarists. They all want to keep this fish at the very beginning because this is very friendly and colorful. But there is a common question out there and that is how many goldfish you can put in a tank.
Well, this answer depends on its various types. Among 11 types of goldfish, 9 types of goldfish need 20-30 gallon fish tank for one fish. More than one fish needs an extra 10 gallon of water. Shubunkin goldfish and comet goldfish both can grow up to 12 inches long. That’s why these types of goldfish need 75 gallon and 50-gallon tank for one fish respectively.
Now let’s discuss this topic comprehensively.
How many goldfish you can put in a tank?
Goldfish Types |
Goldfish Size |
Fish tank size |
| Ryukin goldfish | Full size 8 inches | 20 gallon tank one piece |
| Black moor goldfish | Full size 6-8 inches | 20 gallon tank one piece |
| Bubble eye goldfish | Full size 3-4 inches | 20 gallon tank one piece |
| Celestial eye goldfish | Full size 5-6 inches | 30 gallon tank one piece |
| Comet goldfish | Full size 12 inches | 50 gallon tank one piece |
| Fantail goldfish | Full size 6-8 inches | 20 gallon tank one piece |
| Lionhead goldfish | Full size 6 inches | 20 gallon tank one piece |
| Oranda goldfish | Full size 8-10 inches | 40 gallon tank one piece |
| Shubunkin goldfish | Full size 9-18 inches | 75 gallon tank one piece |
| Telescope eye goldfish | Full size 8 inches | 30 gallon tank one piece |
| Veiltail goldfish | Full size 8-12 inches | 30 gallon tank one piece |
This is the chart from where you may understand the space of goldfish that is needed to thrive. But if you want to put more than one goldfish then you have to provide an extra 10-gallon space for an extra one piece of goldfish.
But this is not the thumb rule for all types of goldfish. There are three types of goldfish that grow more than 8 inches and grow up to 12-18 inches. The fishes are Comet goldfish, Oranda Goldfish, Shubunkin goldfish.
If you want to keep two comet goldfish then you need a minimum of 100 gallon. To keep two Shubunkin goldfishes you need a 90-gallon fish tank. To keep oranda goldfish you need an 80-gallon tank. These tank spaces are most recommended for these types of goldfishes. But you can provide less amount of space also if you don’t want to spend more on the fish tank.
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Can you put more than one goldfish in a 20-gallon tank?
Two goldfishes can be placed in a 20-gallon fish tank forcefully but this is not recommended because goldfish evacuates a huge amount of wastes and 20-gallon tank for one goldfish is enough. Now if two goldfishes are placed in a 20-gallon tank then the nitrogen cycle of fish tan would be disrupted. So try not to place two goldfish in 20-gallon tank. Minimum you need 30-40 gallon fish tank to keep two numbers of goldfish.
Can you put goldfish in a bowl?
Goldfish are hardy fish but this is born not to live in a small bowl. Goldfish can grow up to 14 inches depending on species. But generally, 6-8 inches is the average size of goldfish. Now bowl can’t allow a goldfish to grow up to 6 inches. That’s why the size will be much shorter than the average size of goldfish.
Not only that, but goldfish can live up to 10-14 years in a comfortable fish tank. But in a bowl, it will not live more than 2-3 years. So this is very painful for a goldfish to live in a bowl.
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Do goldfish need a big aquarium to live healthily?
This question is related to the previous question. Goldfish need a bigger tank to grow bigger. If it gets a small space then its growth rate gets stunned.
But there is a scientific explanation for goldfish’s growth rate. According to the source, goldfish produce growth-inhibiting hormones. In a small tank, if you don’t change the water daily then it will prevent the growth of the fish but for a bigger tank this hormone gets diluted and goldfish grows much bigger quickly.
In the goldfish tank nitrogen cycle is one of the main things. Now a bigger aquarium is much better to maintain than a small aquarium. If you have a small aquarium then you need to clear the wastes more frequently than a big aquarium. The nitrate is harmful to a fish that is produced from the nitrogen cycle. That is why you should start with a bigger aquarium if you want to keep this for a long time.
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Final thoughts
I guess from this discussion you have known about the proper tank size of goldfish. Here I’ve given a chart where I’ve mentioned the space that is needed for one goldfish. This chart is not the thumb rule which you need to follow. But if you want to see the highest potential of your goldfish then that space you must provide for your goldfish.
So best of luck & happy fishkeeping 🐟