How Many Neon Tetras in a 10 Gallon Tank

With their electric colors and cheeky personalities, Neon Tetras make a fabulous addition to any tropical aquarium. However, like most tropical fish, they aren’t solitary creatures and prefer to live in schools.

Even when placed in a community aquarium, they believe heavily in safety in numbers and herd together, rarely separating off from their group. 

With this in mind, if you’re thinking about purchasing a Neon Tetra, you’ll need to make sure you’ve got the space for more than one. But just how many Neon Tetras can you fit into a 10-gallon tank? And how many can you fit into a 10-gallon tank that already has fish living in it?

There are multiple things to consider when calculating this. But, for the sake of not just your Neon Tetra’s health, but the health and happiness of the other fish in your aquarium, it’s an important figure to work out. 

Let’s explore these considerations in a little more detail below.

These will help you determine the exact number of Neon Tetras you can keep in a 10-gallon aquarium and ensure that all of your aquatic creatures are as happy as possible after you’ve introduced your Neon Tetras to their new home. 

How big is a Neon Tetra?

The first thing to think about is how big each Neon Tetra will get. Averaging in at around 1.7-inches long, they aren’t huge fish but they do still require plenty of room to zoom around in your aquarium.

Generally speaking, any fish that measures under 3-inches in length needs 1 gallon of water per inch. So, with that in mind, a Neon Tetra measuring 1.75-inches in length would require 1.75-gallons of water. 

Using this simple calculation, we can see that a 10-gallon tank would be able to comfortably house a school of 6 Neon Tetras. 

This calculation carries over to smaller and larger aquariums as well. To make this even easier to work out, we’ve put together this handy chart below. 

Size of Tank

Number of Neon Tetras

5 Gallons

3

10 Gallons

6

15 Gallons

9

20 Gallons

12

25 Gallons

15

Neon Tetras in a Community Tank

While Neon Tetras are peaceful, docile schooling fish, if you’re planning on keeping them in a community tank, it’s important to remember that every other fish in your aquarium has its own temperament and space requirements. 

One of the most popular fish for community aquariums is Bettas. Their beautiful colors, intricate markings, and dazzling fins make them a seemingly perfect pairing with the luminosity of Neon Tetras.

However, Bettas can be aggressive to other fish, and this behavior is usually bought on by a lack of space.

As a general rule, each Betta fish in your aquarium needs 3-gallons of water space. This will ensure they are happy and comfortable which, in turn, will reduce the chances of any fights breaking out between your aquarium’s residents. 

Let’s remember, however, that we are looking at how many Neon Tetras you can fit into a 10-gallon tank without sacrificing the amount of space your other fish have.

Using a single Betta fish as an example, and their space requirement of 3-gallons, you’ll have 7-gallons of water left for your Neon Tetras to live comfortably and to avoid any aggressive behavior between species. 

This gives you the capacity to house 3 Neon Tetras in a 10-gallon aquarium along with one Betta. 

There are, of course, other fish you might want to pair Neon Tetras with. Another popular community aquarium choice is Guppies. These are a lot milder in temper than Bettas, however, they still have their own space requirements. 

If you like the idea of keeping Guppies and Neon Tetras together, you can work out how many you can keep in a 10-gallon tank using the same fish-to-gallon calculations as above. One thing to bear in mind, however, is that Guppies range in size according to their gender. 

On average, a male Guppy measures in at just over an inch. A female Guppy is significantly larger at over two inches in length. That’s double the size of a male!

Knowing the gender and measurements of your Guppies is important when you remember that each fish under 3-inches in length needs 1-gallon of water per inch. 

So, with that in mind, a 10-gallon tank would be able to house 5 Guppies quite comfortably. But what about your Neon Tetras? Let’s take a look at the chart below to make things a little clearer.

Size of Tank
Number of Guppies
Number of Neon Tetras

5 Gallons

1

1

10 Gallons

2

3

15 Gallons

3

4

20 Gallons

4

5

25 Gallons

5

6

The calculations are interchangeable, of course, and you might choose to keep more Neon Tetras than Guppies in a larger tank. Remember, however, that whichever species you’d rather have a larger number of, the same rule applies. Each fish needs 1-gallon of space for each inch of its body length. 

Final Word

As you can see, there is a fairly basic calculation behind working out how many Neon Tetras you can fit into a 10-gallon tank both as a single collection of fish or alongside other community species. 

A 10-gallon tank is relatively small and makes a great addition to any child’s bedroom or for a home with limited space. However, it’s incredibly important that you don’t overpopulate your aquarium with more fish than it can comfortably house.

This will cause aggressive, territorial behavior that can even lead to the death of your fish. 

If in doubt, use the calculations above and make sure that each fish in your tank has at least 1-gallon of water space for each inch of their body length. This will ensure they are all happy and, more importantly, healthy. 

If you’ve got the budget or space to do so, we’d always recommend going for a larger aquarium too. This will give your fish even more room to swim freely, and gives you the scope to add some more into your community aquarium.