What Is the Best Fish Tank Size For Neon Tetra?

If you are in constant search for what is the right tank size for tetras and also need a fish tank size calculator to do the math by your own self, then you’re at the right place!

Neon tetra maintenance requires more than one might imagine. It’s important to consider temperature, tank size for neon tetras, and proper water treatment. Different people have different ideas about how big a tank size for tetras should be.

Some recommend 20 gallons, while others suggest 10 gallons as neon tetra minimum tank size, and still others say 1.5 gallons is. The range of recommended shoal sizes is three to ten.

For newcomers in particular, this contradicting advice can be quite confusing. With our “Neon Tetra Tank Size Guide,” we’ll try to make things easier by offering precise, useful considerations for the neon tetra tank requirements.

Disclosure: This article contains affiliate links. When you follow a link to purchase the products, I sometime earn a commission, at no additional cost to you. Read my full disclosure here

The Ideal Tank Size for Neon Tetras

Although the ideal tank size for tetras depends on the number of tetras you are planning to keep, for 10 to 12 neon tetras, a 20-gallon aquarium makes the perfect home.

This larger tank size for neon tetras allows for the addition of some more peaceful fish in addition to housing a larger school of neon tetras. The higher water volume improves stability when it comes to preserving important neon tetra tank requirements.

Here are some detailed reasons why 20 gallon aquarium is the ideal tank size for tetras;

  1. Less Stress: Fish that have more space experience less stress. In a 20-gallon tank size for tetras, they can relax and display their brilliant colors, but in smaller tanks, stress can cause health problems.
  2. Swimming Freedom: Because neon tetras are enthusiastic swimmers, a 20-gallon tank provides them with lots of room to roam about, which helps to maintain their health and happiness.
  3. Living in a Group: These fish enjoy the company! You can house a larger colony of neon tetras in a 20-gallon tank, which will help them feel less stressed and more at home.
  4. Breeding Space: A 20-gallon tank provides better opportunities for natural breeding and growth if you’re interested in growing the neon tetra family.
  5. Living in a Community: A 20-gallon tank can be compared to a small neighborhood. Inviting other fish companions to coexist with neon tetras can foster a vibrant and varied community.
  6. Fun Environment: You can customize a 20-gallon tank size for neon tetra with plants, ornaments, and hiding places to create a fun environment. They adore an energetic setting.
  7. Clean Water: Larger tank size for tetras are simpler to maintain, such as those that hold 20 gallons. For these delicate tetras, maintain a constant temperature and manage waste more effectively.

What is the Neon Tetra Minimum Tank Size?

In terms of offering neon tetras a suitable home, a 10-gallon tank size for neon tetras is thought to be the neon tetra minimum tank size. Neon tetras are gregarious animals despite their small size, so it’s best to keep them in groups of five or six.

The selection of a 10-gallon tank is not coincidental. Because selective water changes are easier to handle, this neon tetra minimum tank size makes maintenance easier. Bigger tanks also lessen the possibility of notable variations in water quality during regular maintenance.

Furthermore, a 10-gallon capacity which is considered a neon tetra minimum tank size provides plenty of room for setting up tank accents, such as lush vegetation and different hiding places. This reduces the neon tetra tank requirements and improves the overall visual appeal of the setting.

The Neon Tetra Fish Tank Size Calculator

Determine how many gallons of the tank is suitable for your neon tetras ultimately depends on the number of neon tetra fish you are planning to pet.  Thus, the golden rule for neon tetra fish tank size calculator is; the “one inch per gallon” rule.

Neon tetras can therefore swim around in your tank up to 10 inches if it is 10 gallons in size.

More specifically (Using a fish tank size calculator):

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

For instance, if you are keen to keep 10 neon tetras in an aquarium,  then according to the fish tank size calculator, you will multiply the total number of fish by the average size of one fish to know how many gallons of water tank you need.


10 x 1.5= Gallon of Tank

A 15-gallon tank is needed to keep 10 fish! Simple, right?

How Much Neon Tetras Are Enough in an Aquarium?

Here is a summarized table for tank size concerning number of tetras:

Tank Size        Number of Neon Tetras

5-Gallon Tank               3

10-Gallon Tank           6-7

20-Gallon Tank         10-12

30-Gallon Tank          15-20

40-Gallon Tank            20-25

55-Gallon Tank             30-35

Setting up a Tank Size for Tetras

1. Substrate Choice

Since neon tetras congregate in the center, you can choose any tank floor you like. Be careful when selecting pebbles or gravel. Layer it gently at the base of the tank, being careful not to drop any fragile glass as gravel can be a finicky customer. Choose a darker substrate; the tetras will feel more at home there.

Substrate Choice

2. Decor Selections

Your choice of decor is crucial to a happy tetra collection. Add caves, driftwood, and plants for purposes other than aesthetics; they serve as hiding places and replicate the dim lighting that neon tetras prefer. Anubias nana, Java Fern, Amazon Sword, and Java Moss are some of the best plant choices. Not only do these plants add decoration, but they also replicate the murky, black water that neon tetras love.

Decor Selections

3. Lighting Considerations

Use caution when lighting your tank. Avoid using very bright lighting because neon tetras prefer softer lighting. Choose brighter lighting if you have plants in the arrangement to ensure their happiness.

Lighting Considerations

4. Water Addition

After your setup is complete, add fresh tap water. It’s the last detail to finish off your neon tetras’ cozy haven.

Water Addition

5. Filter Selection

In fishkeeping, filters are the unsung heroes. Select a filter that effectively removes debris from your tank without creating a water park. For a 10-gallon tank, a powerhead filter with about 40 gallons per hour (GPH) works perfectly.

Filter Selection

Neon Tetra Tank Requirements

Water Type: Hard, freshwater
Substrate: Sand, rocks, or pebbles
Tank Size: Minimum 10 gallons, add 1 gallon per extra fish
Water Temperature: 70–81°F
Filter: The filter is recommended for better gas exchange but is not mandatory
Acidity (pH): 6.0–7.0pH
Lighting: Keep Lighting as low as possible because they prefer a low-light environment
Tank Setup: Caves and floating plants like Java Moss or Java Fern
Water Hardness (dkH): 2–10dkH
Bubbler: Not necessary if you have placed enough plants and filter
Water Heater: Use one to ensure a steady tropical water temperature

Can You Keep Neon Tetras in a Bowl?

You know, while it may seem like an attractive idea to put fish in a bowl, it’s not the best for our aquatic friends. Fish can be treated unfairly in bowls, which can resemble tiny prisons.

Like tetras, fish require room to roam around contentedly. They don’t have that freedom with bowls. Plus, it’s really difficult to maintain the ideal water temperature in a bowl. Attempting to maintain the perfection of a formal dinner without a well-equipped kitchen is an unsatisfactory endeavor.


In summary, providing a homely environment for neon tetras in their tank is essential to their health. This entails selecting the ideal tank size for neon tetras along with compatible tank mates, keeping the water at the ideal temperature, and providing enough filtration.

Remember to give your fish a healthy diet, give your tank regular maintenance, and keep an eye out for any health problems. Therefore, a vibrant and healthy aquatic community is ensured by thoughtfully designing the tank setup and providing these little guys with the care they require.

Scott Evans

View all posts