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How Many Neon Tetras In A 10 Gallon Tank? Facts & FAQs

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By Lindsey Stanton

Neon tetra Paracheirodon

It can be pretty difficult to judge how many fish can fit in a certain size aquarium. After all, each type of fish usually has different spatial requirements. This is only made harder when you want to set up a community tank with various fish species within it. For instance, if you want to get a 10-gallon tank, and you want to have Neon Tetra fish, you will need to know how many of them can fit.

After all, these little guys are schooling fish, so you cannot keep them alone, but if you have a limited 10-gallon tank, you also cannot cram too many of them into that small space. You could safely fit around 6 Neon Tetras in a 10-gallon tank without issue.wave tropical divider

Neon Tetra – Size & 10 Gallon Tank Housing

Ok, so the first thing that you should probably know is how big a Neon Tetra fish gets. Well, generally speaking, they can grow anywhere from 1.5 to 2 inches in length, with 2 inches being quite rare.

Calculating It

When it comes to calculating how many fish can fit in a certain area, you are better off going with a liberal estimate in terms of fish size, rather than a conservative one, or else you will end up with a tank that is too small. Seeing as Neon Tetras usually do not grow larger than 1.6 inches, to be on the safe side, we will go with a measurement of 1.75 inches.

Image Credit: Kristiana Berzina, Shutterstock

How Many Neon Tetras Per Gallon?

The general rule of thumb with any fish under 3 inches in length, is that they require about 1 gallon of water for each inch of fish there is. Therefore, a 1.75-inch neon tetra would need roughly 1.75 gallons of water. Easy enough right? So, when a 10-gallon tank is in question, you could safely fit around 6 Neon Tetras without issue. 10/1.75 = 5.7, but we can round that up to 6.

Play It Safe

Seeing as we were liberal with our Neon Tetra size estimate, you might even be able to fit 7 of them, but this might be pushing it. Remember, you can fit 7 Neon Tetras in a 10-gallon tank if they are each 1.5 inches long, but chances are that they will probably be around 1.6 or 1.7 inches long each, so to be safe, we would go with 6 of them per 10 gallons.

How Many Neon Tetras In A 10 Gallon Tank With Betta Fish?

Now, Neon Tetras are very peaceful schooling fish. They are fairly calm and docile, and they have a light temperament too. They make for really good tank mates. Lots of people of course want to have more than 1 type of fish in a tank.

One really popular fish is the Betta fish. Yes, Betta fish do have a tendency to be a bit aggressive and territorial, but this does depend on the amount of space they have and the other types of fish they are with. No, you cannot usually have more than 1 Betta fish in the same tank, but Neon Tetra fish and Betta fish tend to get along with each other, granted that you afford them enough space.

betta fish
Credit: panpilai paipa, Shutterstock

A Betta fish should have at least 3 gallons of water to be happy and comfortable. This is actually the minimum recommended tank size for a Betta though we would personally recommend at least 5-10 gallons+.

At any rate, if you have your Betta fish swimming in the same tank as other fish, you will want to provide extra space to avoid any bullying, disputes, and fights between the Betta and the Neon Tetras. Keep in mind we are talking about a 10-gallon tank here.

So, let’s give your Betta fish 5 gallons+ of space to be safe, so there are no fights. This then leaves 5 gallons for your Neon Tetras, which is admittedly not much. Going back to our calculation before, 5/1.75 = 2.8, or in other words, those other 5 gallons can fit roughly 3 Neon Tetra fish.

Therefore, a 10-gallon tank could potentially house 1 Betta fish along with 3 Neon Tetra fish. We were quite liberal here, so you could probably fit 1 Betta with 4 Neon Tetra fish in a 10-gallon tank, but you will have to provide lots of plants and caves for hiding and stress relief, which will help to avoid confrontations.

How Many Neon Tetras And Guppies In A 10-Gallon Tank?

Another nice-looking, peaceful, and mild-tempered tank mate to go with for Neon Tetra fish is the Guppy. Guppies are actually a little larger than Neon Tetras. Guppies do actually differ in size based on their gender.

Males can grow to 1.4 inches long (1 inch is the average), while females are known to get up to 2.4 inches long (2 inches is the average). Once again, when calculating how many fish can fit in a certain number of gallons, it is best to be liberal when choosing the size of fish to calculate with.

Therefore, to be safe here, assuming that you want male and female Guppies, we will use a straight 2-inch measurement for Guppies. Going back to our rule before, fish under 3 inches long usually need 1 gallon of water for every inch of fish. Therefore, in a 10-gallon tank, you could comfortably fit 5 Guppies.

lots of guppies swimming
Image: underworld, Shutterstock

However, we are here to find out how many Guppies and Neon Tetras can fit in a 10-gallon tank, you will need to calculate this. Let’s assume that 4 of the 10 gallons are for Guppies, so you can have 2 Guppies, which means there are 6 gallons left over for the neon Tetras. 6/1.75 = 3.4 (gallons divided by Neon Tetra size).

Therefore, in a 10-gallon tank, you could have 2 Guppies and 3 Neon Tetras (4 Neon Tetras if you want to push it). Or, you could have 3 Guppies (which will take up 6 gallons), and in the 4 remaining gallons, you could have 2 or maybe 3 Neon Tetras.

NOTE: Don’t forget to get a good and reliable filter for your 10-gallon tank! We have covered our top 5 here.

A General Note

If you do have the budget available it is always better to get a bigger tank than 10 gallons if money and space allow. It’s generally always good to give the fish extra space and this also allows for more decorations/plants (remember that plants and decorations take up water space, too).

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How Many Neon Tetras In A School?

Yes, neon tetras are schooling fish, which means that they like to be in groups. No, it’s not like they get lonely per se, because schooling fish travel in large groups in nature to stay safe from predators.

It’s all about safety in numbers. Now, in the wild, a school of neon tetras can consist of dozens, hundreds, or in rare cases, even thousands of individual fish.

However, for it to qualify as a school in a home aquarium, anywhere from 10 to 15 neon tetra fish will do just fine. It’s important to note that they should not be alone.

cardinal tetra
Image Credit: Pixabay

How Many Neon Tetras Should I Get?

As mentioned above, to feel comfortable, neon tetra fish should be kept in schools, and an average school should consist of at least 10 to 15 fish. Now, this is the ideal amount, but it is different from the minimum.

If you are tight on space, and really don’t want too many fish, you can get as few as 4 to 6 neon tetras, and they should do alright.

However, with that being said, it is recommended to get slightly more than that. After all, they are pretty small, so you should not have much of a problem taking care of 10 or 15 of them.

How Many Neon Tetras Can I Put In A 2.5 gallon Tank?

The answer is 1 but it’s really not recommended to house them in a small tank, or alone.

Neon tetras should be in schools of 4 or 6 at the very least, and each fish requires roughly 1.3 to 1.5 gallons of tank space, you should not be using a 2.5-gallon tank for neon tetras at all.

Does Neon Tetra Need Air Pump?

No, in general, neon tetras do not require an air pump. Usually, if you have not overloaded the tank with too many fish, and have adhered to the minimum neon tetra tank size standards, there should be more than enough dissolved oxygen in the water to keep your neon tetras happy and healthy.

The addition of live aquarium plants known for producing large amounts of oxygen can go a long way here too (more on increasing oxygen levels in your tank on this article).

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As you can see, calculating the number of fish that can fit in a certain size tank is not hard. However, it does get a little more difficult when you want to have different types of fish in the same tank. At any rate, Neon Tetras are peaceful and they can be easily housed with a couple some Guppies or Betta fish, just make sure to give them more than enough space, especially where Bettas are concerned.

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Featured Image Credit: Geza Farkas, Shutterstock

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