How Big Do Neon Tetras Get?

Learning how big neon tetras can get will help you choose the best tank size for your pet fish. You may have heard of pet fish outgrowing their tanks, would your neon tetra outgrow your tank? Or, would they remain so small to disappear in a huge tank?

Even as adult fish, neon tetras don’t grow big. They would usually grow to an average size of 1.5 inches (4 cm) and would not commonly exceed this length. As members of the peaceful family Characidae, you should keep neon tetras in schools of at least 10 members.

Mainly, the number of neon tetras you wish to keep will determine the size of the tank you need to purchase. In case you have a small tank that you wish to start with, know how fast neon tetras grow to help you make the right decision.

What is the Maximum Length a Neon Tetra Can Grow?

The maximum length a neon tetra can grow is around 2.0 inches (6 cm). However, you will rarely see a neon tetra reaching that length. Most neon tetras remain within the length of 1.5 inches (4 cm).

Do Female Neon Tetras Grow Bigger than Males?

The difference in structure (sexual dimorphism) between the female and male neon tetras is slight but noticeable. When it comes to size, the females tend to have a belly slightly larger than the male.

Another noticeable difference between male and female neon tetras is in their colorful stripes. The stripes in females appear bent compared to the males’ straight stripes. Although, the males seem to have more vibrant coloration and longer fins.

How Fast Would a Neon Tetra Grow?

Most neon tetras will reach the size of a full-grown adult (around 1.5 inches) within their first year.

In the first few months, your neon tetras would still be small as they would grow quite slowly at first. That is, they may even take up to 2 months to reach a quarter of an inch even in the best tank condition. After that, their growth rate will increase.

Since you already know what to expect of the size of your neon tetras, their growth rate will also help you to know if you need a new tank or not. Of course, neon tetras are schooling fish and you’ll need to keep many of them.

What is the Ideal Number of Neon Tetras that You Can Keep in a Tank?

Most aquarists will prefer to keep a school of 10 neon tetras. However, depending on your tank size and what pleases you, you can adjust the number of neon tetras you keep.

For instance, if your tank is small, you can choose a school of 4 – 6 neon tetras. On the other hand, if you have a very large tank, you may decide to choose 15 – 20 members or even more.

The fact remains that whichever you choose, your neon tetras will be happy with their company. And, do not isolate neon tetras. Keep the minimum number at 4 and do not go below.

Keeping neon tetras in schools is beneficial to them as it reduces their stress level. They feel more comfortable swimming in large groups. Thus, they will live longer in schools than in isolation.

Will Tank Size Affect How Big a Neon Tetra Can grow?

At maximum adult size, the neon tetra is still a very small fish. So, it is unlikely that a tank will affect how big a neon tetra can get. A single neon tetra can swim comfortably in a 1-gallon tank.

But you can’t keep a single neon tetra, therefore, the ideal number of 10 neon tetras will require 15 – 20 gallons. If you decide to keep a lower number of about 6 neon tetras, then a 10-gallon tank should serve.

When choosing a tank for your neon tetras, go for the taller fish tank. This is because neon tetras swim the middle water column, hence a taller aquarium will provide swim space. Keep this in mind always.

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Can You Keep Neon Tetras in a 5-gallon tank?

You can possibly keep your neon tetras in a 5-gallon tank. However, this is not recommended. If you must, then go for 4 – 5 neon tetras and choose the taller 5-gallon tank. Remember to add enough rocks and plants to improve the oxygen in the tank.

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Several setbacks are surrounding keeping neon tetras in a 5-gallon tank. Expert aquarists know this and avoid it.

If you have your neon tetras in a 5-gallon tank, you must pay special attention to keep your pet fish healthy. Thus, you must make sure not to add excess feed in the tank, install a water filter and heater, weekly tank water changes, and have enough live plants.

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Regular maintenance of small tanks is necessary to keep your fish healthy. Check the water parameters as often as possible because it is very easy for water conditions to deteriorate.

How Many Neon Tetras Can You Have in a 10-gallon tank?

A 10-gallon tank can comfortably house 4 – 6 neon tetras with enough room to swim around. You can also have up to 8 neon tetras in your 10-gallon aquarium. However, you will need to pay extra attention to your fish as in a 5-gallon tank.

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The thumb rule to choosing a tank for your neon tetras is that a 1.5-inch neon tetra will require a swimming space of 1.5 gallons. Since you are not sure how big your neon tetras will get, it is only advisable to go with what works best.

This is the reason a 10-gallon aquarium is the least recommended for keeping a small school of neon tetras.

How Many Neon Tetras Can You Keep in a 20-gallon Aquarium?

You can comfortably keep a school of 10 – 12 neon tetras in a 20-gallon tank. This is the ideal tank size for keeping neon tetras. An ideal school of neon tetras should consist of at least 10 members.

This tank size creates enough room for your neon tetras to swim around freely. It will make your pet fish feel more secure than smaller tank sizes.

It is only advisable that you go for a 20-gallon tank when planning to keep an ideal school of neon tetras. However, if your budget does not allow it, you can still go for a 10-gallon tank with 4 – 6 neon tetras.

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Can My Neon Tetras Grow Together with Other Fish Species?

Yes, you can keep your neon tetra in a community tank with compatible tank mates. Though, the pairing strategy has more to consider than just compatibility.

A popular tank mate for your neon tetras is the betta fish. The two fish species are colorful and do not grow too big. Although bettas are fairly larger than neon tetras. With enough swimming space in the tank, they most likely will live comfortably with each other.

Deciding to add tank mates for your neon tetras means that you have enough space in your tank.

And, you should know that more tank mates mean fewer neon tetras. Of course, you do not want to overcrowd your tank.

If you have a 20-gallon tank and you want to have neon tetras and guppies in it, then you should have 4 – 6 neon tetras and 4 – 6 guppies. A 20-gallon tank provides space for 10 – 12 fish. Hence, the more guppies you have, the fewer neon tetras.

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In What Aquarium Conditions Can Neon Tetras Grow Conveniently?

The best aquarium conditions to ensure the growth of your neon tetras include:

  • Water type: Make sure you put your neon tetras in a freshwater tank. Since they are freshwater fish in the wild.
  • Water temperature: Keep your tank’s water temperature constant and ideally between 22C and 25C. It may be slightly higher or lower, but don’t let the water fluctuate so much.
  • Water Hardness: Keep the hardness of water between 1 and 12 dGH (degree of general hardness). The benchmark for ascertaining mineral range in determining the quantities of ions of calcium and magnesium present.
  • Water pH level: The pH level of the water should always be between 5.0 and 7.5. Remember that keeping it at average position is always the best.
  • Vegetation: Your neon tetras will appreciate extra vegetation within their tank. They prefer making use of shaded places in the aquarium.

You must understand that the condition of the aquarium can have a great impact on the growth of your neon tetras. Therefore, you should pay attention to the tank conditions listed above to help your fish grow.

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How Can You Help Your Neon Tetras Grow?

There are extra care routines that you can incorporate to help your neon tetras grow and flourish effortlessly in the aquarium.

Feed Your Neon Tetras Right

This is where you start! Feeding your pet fish right means giving them a balanced diet. Of course, as omnivores, neon tetras eat a variety of food substances from plant to animal materials.

Do not feed them from only one food source. Try to mix things up and watch your tetras grow healthily.

Keep Your Water Nitrate Level at Zero

Yes, aim at keeping the nitrate level to zero. Things can go wrong quickly. If your aquarium water nitrate jumps above 20 parts per million, then your neon tetras are likely not to grow as you expect.

Nitrates are simply pollutions in your tank caused by decaying organic materials following the nitrogen cycle. It makes your fish weaker and unable to grow. So, keep the level of nitrates in your aquarium as low as possible to ensure the proper growth of your neon tetras.

Practice Frequent Water Changes

Your tank can be harboring phenolic compounds which can inhibit the growth and development of your fish. Changing your aquarium water more regularly can help provide a solution. It will keep the concentration of phenolic compounds in check and your fish will experience proper growth.

Do Not Overpopulate Your Tank

You want your tank bustling with activities; hence you add so many aquarium species in your tank. Just so you know, this practice can hinder the growth of your fish in many ways. Talk about the organic waste generated in the tank reducing water quality, competition for food, etc.

All these can cause stress to your neon tetras as part of the community tank. Stress generally hinders growth in fish. So, if you wish your pet fish well, avoid overpopulating the tank.

Use Only the Best Tank Mates for Your Neon Tetras

Some tank mates may seem to be good but are not the best for your neon tetras. Scalars, guppies for example are dominant species and will snatch food and take up more space from your tetras.

This will only leave you with unhealthy neon tetras lacking proper growth. So, if you must have tank mates for your neon tetras, go with the best compatible such as betta fish.

Keep Eyes on Your Fish

How would you know if your fish is growing healthily in the first place or not? Simply by taking out time to observe them. The best way to observe your fish is by doing so from a distance first before going close to the tank.

This is because your fish is likely to change behavior once you come too close. When you’re done checking their behaviors, you can now go close to check for injuries and size.

In the End

There is so much attached to the growth of neon tetras. And, very importantly, you have roles to play to help your neon tetras reach their expected adult size. This page highlights the average growth size and rate of your neon tetras, the need to choose the right tank size, and give proper care.

Therefore, you should prepare very well if you want your neon tetras growing comfortably in your tank.