Are you trying to decide the fish tank size needed for your goldfish? Want to know how many goldfish can fit in your aquarium? Goldfish are freshwater aquarium fish that can grow pretty big. Goldfish can grow up to 12 inches! Your goldfish will suffer if you overcrowd your aquarium with too many goldfish. In fact, goldfish are cold water fish that can live in ponds- just imagine the space they need to live happily. Goldfish are also messy eaters and can produce a lot of waste so you will need a larger aquarium to keep them healthy.
When trying to decide the correct aquarium size for your goldfish, you need to take that into account the type of goldfish you will be housing. Are you housing juvenile goldfish, if so, you can fit more goldfish in one tank but be prepared to transfer your goldfish to a larger tank as they grow. We’ve created a Goldfish Tank Size Calculator below to calculate the number of goldfish you can put in your aquarium.
What Size Tank Do You Need for 1 Goldfish?
One goldfish will need a minimum of 3 gallons per goldfish. This is for goldfish that are 2 inches or smaller in size. However, that doesn’t mean your goldfish will live happily in a 5 gallon aquarium. Goldfish can grow rather large. The common goldfish can grow up to 12 inches long. If you put your goldfish in a small aquarium, you will stunt your goldfish growth.
What Size Tank Do You Need for 2 Goldfish?
For two goldfish, you need at least at least a 10 gallon tank.
How Many Goldfish Can Fit in a 5 Gallon Tank?
You can fit 1 goldfish in a 5 gallon tank. This is assuming your goldfish is less than 2 inches in size. However, it’s not advisable to house goldfish in five gallon aquariums. Goldfish are messy eaters and will need a lot of space. Keep in mind that if you put your goldfish in a 5 gallon aquarium, be prepared to transfer your goldfish to a larger tank in the near future. If your goldfish is larger than 2 inches, don’t even try putting your goldfish in a 5 gallon tank.
How Many Goldfish Can Fit in a 10 Gallon Tank?
You can fit 3 goldfish in a 10 gallon tank. This is assuming your goldfish is less than 2 inches in size. If your goldfish is larger (2-6 inches), you can fit only one goldfish in a 10 gallon tank. Keep in mind, a 10 gallon aquarium is not a big enough aquarium for goldfish. Be prepared to transfer your goldfish in a larger aquarium as they grow.
How Many Goldfish Can Fit in a 20 Gallon Tank?
You can fit 6 goldfish in a 20 gallon aquarium. This is assuming your goldfish is small, measuring less than 2 inches in size. For goldfish measuring 2-4 inches, you can fit only 3 goldfish in a 20 gallon aquarium. While for larger goldfish measuring 4-6 inches, you can fit 2 goldfish in a 20 gallon aquarium. For goldfish measuring larger than 6 inches, you will need a larger aquarium than 20 gallons for your goldfish.
How Many Goldfish Can Fit In Your Aquarium?
Use the Goldfish Tank Size calculator below to compute how many goldfish can fit in your aquarium. Input the Aquarium size and select from the drop down menu the size of your goldfish.
This calculator is for goldfish only fish tank. If you are creating a community tank of cold water aquarium fish, then you will need to make adjustments because you don’t want overcrowding in your fish tank.
Table: How Many Goldfish Can Fit in Your Aquarium
| Goldfish Size | 10 Gallon Aquarium | 20 Gallon Aquarium | 30 Gallon Aquarium | 50 Gallon Aquarium |
|---|---|---|---|---|
| Small Goldfish (less than 2 inches) | 3 | 6 | 10 | 16 |
| Medium Goldfish (2-4 inches) | 1 | 3 | 5 | 9 |
| Large Goldfish (4-6 inches) | 1 | 2 | 3 | 5 |
| Extra Large Goldfish (Greater than 6 inches) | 0 | 1 | 2 | 4 |
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Everything You Need to Set-Up Your Goldfish Aquarium
- Hanging Filter
- Gravel (15 lbs for 10 gallon tank)
- Rocks: Natural rocks and/or Rock caves
- Fun aquarium Decor: Sponge Bob
- Aquarium Glass Cleaner
- Aquarium Gravel Cleaner
- Water Conditioner (dechlorinator)
- Fish Flakes
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