How Many Neon Tetras In A 3 Gallon Tank?

The neon tetra is a small fresh water fish whose origin traces back to South America after its first discovery in the Amazon jungles. It is one of the most popular fish amongst fish keepers. Its popularity is a result of its vibrant colors, energetic temperament, and ease of care. Neon tetras are bred in captivity and each month, there is a significant number of them being sold. Before you decide to get neon tetras, you need to learn and have vast knowledge about their care. How many neon tetras you can keep depends on how much space you have in your tank. This article is specifically addressing the question “how many neon tetras in a 3 gallon tank?” Neon tetras are schooling fish, and therefore should be kept in numbers, if you are to use a 3 gallon tank, you can only keep 1 maybe 2 neon tetras. This is really not a good idea as your fish will become stressed and will likely die. This article highlights everything you need to know about neon tetra.

large shoal of neon tetras

Neon Tetra Care Guide

Neon tetras are quite common among fish keepers for the fact that they are colorful, simple to care for and enchanting. They are non-aggressive, schooling fish that spend most of their time in the middle of the water column. For you to get the best of them as your pets, you must provide the right care and optimal environment for them to thrive.

Neon tetras have been in the aquarium market for quite a long and therefore are usually available at any live fish store throughout the year. The fact is, neon tetras are relatively easy to care for and breed in captivity. When thinking about rearing neon tetras, consider those from aquarium farms as opposed to wild-caught species since they have adapted the living conditions in the aquarium.

(Read our article How To Care For Neon Tetras for a more in depth guide on caring for these wonderful fish.)

Speaking of neon tetras, do you even know what they look like? Would you distinguish them from other fish? Let’s find out

What Do Neon Tetras Look Like?

Neon tetras are beautiful and their sensational coloring is what attracts many people. The first thing you note about them is the blue line that runs from its eyes to the adipose fin. In addition to this, they have a red stripe starting from the middle of the body to the caudal fin. This coloration is for identity and helps them locate each other in murky water conditions. They also have a shiny silver abdomen.

Despite the numerous coloring, neon tetras are transparent, an adaptive property that helps them hide from predators. At some point when they feel threatened, they tend to turn off the bright color. When unwell or sleepy, the colors also tend to fade.

Neon tetras are often confused with cardinal tetras for their striking similarities. They both have red and blue stripes. There is however a distinction between the two. With cardinal tetras, the stripes run the entire length of the body unlike in neon where it goes halfway. Cardinals are also bigger and grow up to 2 inches.

Cardinal Tetras like the one pictured are often mistaken for Neon Tetras

Body Type

Neon tetras have an optimal growth of up to 2.5 inches, on average, most of them are around 1.5 inches. They can be characterized by their rounded nose, spindle-like body, and their large eyes.

Neon Tetra Lifespan

Wild neon tetras can live up to 8 years for they live in their natural setting. The lifespan is however lesser to about 5 years in aquariums.

Varieties of Neon Tetra

There are many varieties of neon tetras that result from captive breeding.

  • Longfin- as the name suggests, this breed has fins that almost double those of the wild form in length.
  • Albino- the name comes from the fact that they lack the red and blue color. Their lack of pigmentation gives them a pearly white, shimmery look. They also have pink eyes.
  • Golden-they quite resembles albinos to some extent, they are however not missing all their coloration. In many instances, they lack the blue color in their heads and backs but have the red stripe. They can also be identified by the striking blue color of their eyes.
  • Diamond head- instead of the blue and red stripe down the sides of the body, this breed only has a bright blue diamond shape on its heads.

Neon Tetra Optimal Conditions and Tank Requirements

Before setting up an aquarium for neon tetras, you should first understand their natural habitat then try and replicate it as much as possible. The important thing to note is that neon tetras are community fish, which means that they thrive living as a group.

They are mainly found in the Amazon River that flows through dense canopies and is thus exposed to little or no sunlight. Your aquarium therefore should have many plants. Use driftwood and dark substrates to add the intensity of the darkness.

Tank Conditions

Neon tetras are very sensitive to changes in water conditions. For this reason, do not use newly cycled tanks, use an established and mature tank.

The optimal tank conditions are as follows:

  • Temperature- between 72-76 degrees F (22.2-24.4 degrees Celsius)
  • pH- a level below 7.0 and above 6.0
  • Ammonia -0 ppm
  • Nitrate- 0 ppm
  • The tank should be mature, cycled for at least 4 months
  • Get to establish a good nitrogen cycle
  • Consider having a large substrate the fish cannot eat
  • Plant many plants

How Many Neon Tetras Should You Get?

Keep neon tetras in a large group that you can manage. Keeping them in too small numbers makes them stressed and unhappy. The absolute minimum number of neon tetras you should have is six. Schooling for neons gives them a sense of security and hence grow well. It is recommended that you have at least 15 of them for best results.

What Tank Size Do You Need?

The size of the tank depends on the number of fish you are rearing. The minimum recommended tank size is 10 gallons which would accommodate a small group of neon tetras.

Neon tetras look their best in a bigger tank. If for instance, you are having a group of 15 fish, consider a 20-gallon tank. 

A 3 gallon tank is simply too small for neon tetras to be happy.

What could be the issue if someone kept neon tetras in a 3-gallon tank?

Anyone who understands tetra species knows that neon tetras are shoaling fish and should really be kept in groups of 6 or more. It is therefore quite impossible to compact them in a small area.

Having a smaller tank means a smaller number of fish. The fish will tend to feel insecure and stressed. If the fish gets aggressive, they don’t have a good number to pick on. Having a larger group is important so that the aggression spreads out.

With a 3 gallon tank, you can really only have 1 neon tetra. That one fish wouldn’t even get enough space to play and you can’t add more items like tank decorations. If you are a fish enthusiast and you love neon tetras, consider a tank not less than 10 gallons.

Young fish growing in a small tank are not comfortable and could have issues such as slow growth rate, spinal deformities, and other issues affecting their development.

What could be kept in a 3-gallon tank?

A 3-gallon tank is best suited for fish that can live on their own. The best option, in this case, would be a betta. They do very well living on their own and look beautiful too!

Betta fish do very well living on their own

Feeding Neon Tetras in a tank

Neon tetras feed on both meat and plant matter in their natural environment, they are therefore omnivorous. They are not selective feeders and do eat a variety of food including pellets, flakes, and live-giving their keepers an easy time.

You must provide your fish with high-quality feeds. For example, pellets and flakes are the main diets, you should therefore provide the highest quality of them. Supplement the same with live or frozen ones like blood worms, daphnia, tubifex, and shrimp.

You can also grow your food such as vegetables to incorporate into their diet.

You should feed your neon tetra in small quantities of food to avoid overfeeding. The pieces should also be small to avoid giving them problems when swallowing.

Young adults should be fed twice a day, the frequency reduces as they grow until you feed them once a day.

Breeding Neon Tetras

Breeding can be quite a challenge since you need to provide specific water conditions to stimulate the mating season. If you are a beginner, you shouldn’t try breeding them.

When trying breeding, you first need to determine the gender of the fish. Male neon tetras tend to be slimmer, longer, and have a flat stomach. They are identified by a straight blue strip. Females on the other hand are rounder; their round stomach causes their blue strip to appear bent.

How many neon tetras in a 3 gallon tank - Conclusion

Fish experts recommend bigger aquariums for neon tetras. Smaller aquarium tanks might be easy to maintain, but they pose significant challenges in attempting to stabilize the environmental conditions that suit the fish species. A 3-gallon tank is ultimately not the best for this species of fish: it doesn’t provide enough room considering neon tetras want to live in groups rather than as a single fish.