(Solved) How Many Neon Tetras Can Go In A Tank? +Tank Size Chart

Have you ever wanted to see plenty of fish in your aquarium?

This feeling can be stronger, especially if your aquarium has extremely beautiful fish like neon tetras. These are tropical freshwater fish that are small and shiny. 

Many fishkeepers consider neon tetras as one of the best fish pets since they are active, peaceful, and tough.  So, you can keep plenty. But how many neon tetras can go in a tank?

I have answered this question and more in this article. So, keep reading to help yourself make the most stunning aquarium with tons of tetras.

Aquarium Size Guide For Neon Tetras – How Many Neon Tetras Can I Put In A Gallon Tank?

Neon tetras like to be in a group, and they usually swim around in a group of 5 or 6. So, get a tank of at least 5 gallons. Nonetheless, it is okay if it is smaller even; you may have to reduce the number of fish.

To give you a clear idea about this, here’s a size guide table that tells how many neon fish can fit based on tank size:

Tank Size (in gallons)Number of Neons
2.5 1 or 2
1 or 2
3 to 4
4 to 5
10 5 to 6 
15 6 to 8
20 10 to 12
29 15 to 18
30 15 to 18 
40 20 to 26
5528 to 36

how many neon tetras can go in a tank?

What Size Tank Do They Need?

Neon Tetra fish have a slim build, so we can maintain the golden rule: keep one inch of fish per 1 gallon of water. 

Using this formula, the total number of tetra fish you can keep in an aquarium is divided by the average size of your fish. So, you can add one tetra fish for every one gallon of water.

Total Tetra Fish in the Tank = Gallons of Water/ Size of Fish in Inches

For example, you can add up to 5 fish in a 10 gallons tank. You should also consider other factors like tank mates and the male-female ratio before keeping them.

What if you Put Too Many Neon Tetras in a Small Gallon Tank?

If you put too many neon tetras in a small gallon tank, it can lead to overcrowding. It will give off excess waste, which will contain ammonia and nitrates. 

These contaminants can dirty your tank quickly and make it cloudy. Plus, exposing your fish to them even for a short time can cause long-lasting damage. Sometimes, it can even kill your fish.

It can lead to an algae boom since algae thrive on nitrate and ammonia. With the algae and the crowd, it can become harder for the fish to swim freely or breathe. Although tetras are peaceful, overstocking can make them aggressive.

What Happens When There Are Too Few Neon Tetras in a Large Gallon Tank?

If the tank is big, you should keep at least six fish since they like to live in a group.

Neon Tetras: An Overview

Paracheirodon Innesi, the neon tetra, is one of the few fish species that is very easy to maintain. They are also very beautiful with their attractive and sensational colors. Commonly, they have blue, red, and translucent colors.

YouTube video

They can grow about 1.5 to 2 inches large normally. However, they can grow up to 2.5 inches under certain conditions. Owing to their small size, you do not need an extravagantly large aquarium to keep a school of tetras.

It is also very easy to feed them since you need to give them basic protein food. You can feed the fish brine shrimp or blood worms once or twice a day, and they will do alright.


  1. Can You Overstock on Neon Tetras?

    No, even though neon tetras are hardy, you should not overstock them.
    Overstocking makes the tank too dirty too soon, and it can cause health issues in the fish.

  2. Does Neon Tetra Need to Be In Groups?

    Yes, neon tetra likes to be in a group. They swim in the tank in a school of 5 or 6 fish.

  3. What Is the Minimum Size of a Tank for Neon Tetra?

    Ten gallons is the recommended tank size for neon tetras. However, if you can, go with 20 gallons, so that you can keep some decor inside the tank as hiding places for the tetras.

  4. Can You Just Keep Female Neon Tetra?

    Yes, you can keep just female neon tetra, although you cannot tell the gender until they are four months old.

  5. Can You Just Keep Male Neon Tetra?

    Yes, you can keep just male tetras. However, it would be better to keep both males and females together.

    Why? Male fish usually don’t usually get along with each other. If you only wish to keep one fish that is a male, then it is important to keep him with at least 3-5 females.

Wrapping Up

Neon Tetras are easy to maintain and beautiful to look at. Remember to take good care of them!

Now that you know how many neon tetras can fit in your tank, go ahead and fill it up with these beautiful creatures!