How to Care for Neon Tetras: A Complete Fact Sheet, Breeding, Behavior, and Care Guide

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Neon Tetras are usually within the first ten species of freshwater fish that most home aquarium keepers start with. They are fairly peaceful, elegant fish that pack a lot of color and personality into small bodies. 

These are somewhat torpedo shaped fish that have compact, translucent to clear fins and tail. 

Insofar as color, both males and females are mainly silvery, iridescent grey in color. As they swim around, you may see a startling bright powder blue line emerge over their eyes that goes about ¾ of the way through their body. Keep watching, and that line disappears with the change in lighting conditions! 

neon tetra front swimming

Next, a bright red stripe starts on the lower half of their body and then extends upward and into the tail region where it fades a bit to orange. Finally, the underside of the Neon Tetra’s body is usually either white or a very light grey.

These fish will usually swim in groups quickly and gracefully around the tank. Even though they are fairly small, watching a school of them is fascinating because their colors shimmer and change as they move around from one spot to another. 

As with other aquarium keepers over the years, I have returned to Neon Tetras several times because they are colorful, and mostly peaceful fish. While they are a bit fragile, they still give the home aquarist a good chance to maintain and develop new skills. 

Quick Intro to Neon Tetras

FamilyCharacidae
Scientific NameParacheirodon innesi
Other Common NamesNeon Fish
Care LevelEasy to moderate

Originally, Neon Tetras were taken from both clear and tannin-rich streams of the Amazon Basin in countries such as Brazil, Columbia, and Peru.

Unlike several other fish that are popular among aquarium keepers, Neon Tetras usually do not take hold in foreign habitats. As such, they are not considered an invasive species in the United States and are legal to keep in most, if not all states. 

Neon Tetras look fairly similar in color and shape to Cardinal Tetras. They are also very similar to Glass Tetras and other smaller members of the tetra family. Even though Neon Tetras are considered one of the most peaceful fish for freshwater aquariums, they are distantly related to piranhas.

Temperament wise, I usually place Neon Tetras somewhere between the Glass Tetras and Skirt Tetras. The latter are still fairly peaceful fish, however they have a bit more body size and will bash or nip if they have to.

None of these fish are anywhere near as aggressive as Buenos Aires Tetras, however, you will quickly see similarities in their swimming patterns and eye movements. 

Optimal Water Conditions For Neon Tetras

Water Temperature70 – 78 degrees Fahrenheit
Water Flow RateSlow to medium with airstones to gently increase and even out water circulation
pH6.0 – 7.0
HardnessSoft
Aquarium Salt RecommendationsAquarium salt can be used in small amounts for preventing illness, and also for treating active infections

Determining the amount for new fish can be tricky. I usually don’t purchase Neon Tetras from a local pet store until I have watched them swimming in the tank for 2 to 3 days. If they do well, that means the water in the tank is what they are accustomed to. 

From there, I just take the salinity reading in the bag and set my quarantine tank to that salinity level. Then, during the quarantine level, I slowly adjust the salinity level to match the community tank they will be moving into.

  • Tannin Recommendations: Yes, blackwater is highly recommended
  • Other Water Chemistry Needs: Along with being within the tolerance range for Neon Tetras, stable and good water quality is very important. Even slight changes can cause illness and death in these fish. 

When adding new fish, it is best to use a quarantine fish tank so that you can make changes slowly between the parameters in the merchant’s tank and your community tank. Never place Neon Tetras directly into the quarantine tank from the transport bag. 

Let the bag float in the tank for about 15 minutes to allow the water temperature to adjust. During this time, you can add some water from the quarantine tank to the bag so the fish can begin adapting to it. 

Be wary of bag water parameter readings that fall outside the optimal pH and hardness readings for Neon Tetra fish, especially if you aren’t able to watch the fish for a few days before buying. 

Ammonia and other chemicals dissolved in the water can easily throw the bag readings off. If the fish show signs of distress, you can try shifting into their optimal range. 

Usually, I also request an additional gallon of water from the merchant’s tank in case the fish show signs of distress and I need to set them up in a bowl for a more prolonged acclimation (similar to what I use for saltwater fish).

I also always ask which water conditioner the merchant uses in their tank. If it differs from what I use in my tanks, then I check for compatibility between the two products and take adjustments between the two formulas into account during the acclimation and quarantine processes.

Tank Setup

Minimum Tank Size20 gallon
Optimal Tank Size55 gallon
Optimal Tank ShapeNeon Tetras will do fine in both shallow, deep, and mid-depth tanks.
Recommended Filter TypeNeon Tetras look like sturdy little fish, however, they can be quite fragile. They will do best in a tank with bubble up filters, under gravel filtration systems, or others where there is not a strong inlet that can pull them into it.
Extra Air Flow and How to ProvideYou can use airstones and curtains with Neon Tetras, however it is best to keep the air flow from each device in the lower to mid ranges.

I agree with most aquarium keepers that say it is best not to use Neon Tetras as a first fish in a newly cycled tank. Wait for the water chemistry to stabilize to a point where you need to little more than replace water lost through evaporation.

Depending on the size of the tank, this may take just a few months (for a 10 gallon tank), to around 18 months for larger tanks. 

Since Neon Tetras are extremely sensitive to water chemistry changes, you should test nitrites, nitrates, ammonia, pH, hardness, and salinity (only if you are using aquarium salt, water conditioners, or antibiotics that contain it) levels on a weekly basis. Make adjustments slowly over the course of 2 – 3 days to reduce shock on the fish as much as possible.

Later on, as the tank matures in terms of water chemistry, you may be able to take a good guess at its quality and stability just by looking at the fish.

Neon Tetras that are doing well and comfortable will display their electric blue stripes and overall coloration will appear bright and shiny. If the fish become dull or reduce activity levels, it is a sign that the water chemistry is drifting out of their comfort range.

Creating the Landscape

two neon tetras in aquarium

Neon Tetras originate in streams that are usually rich in organic matter that turn the water brown or black. This includes plants that shed a lot of leaves as well as driftwood that also leaches tannins into the water.

Best PlantsAponogetons, java moss, and other fast growing plants that will do well in low light conditions and in acidic water.
Best LightingLow to medium lighting with plenty of shady areas.
Best DecorationsDriftwood, rounded rocks, and caves. Since these fish are also very agile, they will do fine with toys that have holes to swim in and out of. Just make sure there are no sharp edges around the holes. You can also make custom rings from aquarium tubing that are much safer and eliminate the risk of the fish getting trapped in them.
Decorations to AvoidFake plants with sharp edges that can cut into the fish’s delicate slime coat. It is also best to avoid air fed clam shells or other moving toys that the fish can get trapped in.

Physiological Considerations

Maximum SizeA little over 1.5 inches. Older fish will also be a bit heavier and longer.
Rate of GrowthReach full size in about 1 year.
Lifespan5 – 8 years
TemperamentFairly peaceful, however, they can become aggressive among themselves or with small fish if they feel insecure.
Preferred Tank RegionMid region, however they will go to top and bottom in search of food.
Scale Thickness Neon tetras do not have scales. As such, you will need to be careful when choosing antibiotics for them. 

Gill Considerations

From a disease perspective, Neon Tetras tend to have fairly sturdy gills. They will do well enough in slow-moving water and do not require fast-moving water to keep their gills healthy.

On the other hand, their gills are physically small and quite fragile. They will turn red quickly if the water chemistry is wrong, and also swell up. This is part of what makes caring for these fish a bit tricky.

Swimbladder Considerations

These are not deep-bodied fish, so they are not prone to mechanical swimbladder problems that require feeding peas. I still introduce their food below the water level to reduce the risk of the fish taking in air while they eat.

Other than that, Neon Tetras do come down with internal infections that cause swelling and other signs of swimbladder disease. 

Fin Shape Considerations

Even though Neon Tetras are fast swimmers, they are quite weak in terms of their ability to fight a moving current. It is best to keep them in tanks with gentle, but steadily moving water currents.

Neon Tetras are also quite capable of jumping out of the water, so it is best to keep a tight-fitting lid on their tank.

Society

For the most part, male and female Neon Tetras have the same kinds of behaviors. They are both fairly peaceful and are mostly schooling fish. There is no specific ratio of male to female, however, I try to keep mine at 1 male to about 5 or 6 females.

Insofar as other species, Neon Tetras will swim and eat with other fish that are around the same size as them. Usually, these fish will not attack others in the tank, nor will they go after freshwater shrimp, snails, or other creatures. 

Even though it is rare, you may come across a Neon Tetra that nips fins or chases other fish. This can happen with both male and females of the species. Here are some things to look for:

  • Usually, the biggest fish in the school will be the one that turns into a bully. As with many other species, Neon Tetra bullies will chase weaker or smaller fish. The males will chase each other more when females about to lay eggs are present. They will also chase females, however that will be more focused on getting the female to take interest in a particular plant, or a good spawning place.
  • Before Neon Tetras move in for an attack, they will splay their fins, and are also likely to circle each other. Their actions are usually much faster and directed to the mid-body of their adversary. Usually, these fish won’t lock mouths together like tiger barbs, but it can happen. 

 If you have a bully fish in the tank, there are a few different ways to approach the problem:

  1. Try to get 4 more fish that are the same size as the bully so they can develop a pecking order among themselves. Neon Tetras can feel very insecure when there are not enough of their kind in the tank, or not enough aquarium fish of the same size.
  2. Some aggression may be coming from food scarcity or insecurity. Try feeding tetras three smaller meals a day instead of two.
  3. Add more territorial markers or decorations in the tank. Sometimes, a bully fish will want a live plant or some other object for the purpose of marking territory. If you notice the bully hanging around one specific plant, try putting more of that type in the tank. This way, the other fish can claim its territory, or it will have another place to hide.
  4. If the bully continues to chase and pose a threat to other fish in the tank, you will either need to put it in a tank by itself, or set up a partition where it can live by itself. Emotionally, this can be very hard on the bully at first, but it will eventually get along just fine without the company of other creatures. 

Gender, Breeding, and Reproductive Considerations

It is fair to say that Neon Tetras are some of the most heavily captive-bred fish in the hobby aquarium trade. Genetically speaking, you are not likely to get reproductively viable fish at the hobbyist level. Even though your Neon Tetras are likely to spawn, it is best not to try and raise the fry to adulthood. Many times, they will wind up being misshapen creatures that will not be as healthy as the parents. 

If you are interested in raising Neon Tetras, start off with fish that are certified healthy enough and viable enough for breeding. These fish may cost a bit more, but it will be worth it in terms of the resulting good health and appearance of the offspring. 

Once Neon Tetras reach maturity, females will show deeper or fatter bellies when they have eggs ready to release. You may notice males tending to hang around the female more often, as well as an increase in chasing behaviors. 

If you intend to raise new tetras, then you will need to move prospective parents into a breeder tank. This tank should start off with the same water chemistry as the community tank. 

Use a bubble up filter for filtration. Be sure to place a nylon stocking over the vents so that eggs and fry do not get pulled into the filter later on.

Insofar as decorations, you can use breeding grass and carpet mosses to help hide the eggs from parents that will consume them almost as soon as the female releases them.

multiple neon tetras in a fish tank

 Introduce the female that you know is about to release eggs, and at least one male at sunset. This gives the fish time to adapt to the new setting overnight.

If the fish to do not spawn within a day or two, do a partial water change to generate a sudden drop in nitrate levels. Since these fish usually spawn after it rains in the wild, this will mimic the same sudden water change. 

After spawning, it is best to remove the parent fish and put them back in the community tank as quickly as possible. Leave the eggs in the breeding tank, as this will now serve as the nursery.

If all goes well, somewhere between 60 and 130 eggs will hatch in about 24 hours. The fry are very sensitive to light and will jump or try to swim if you shine a light on them.

When fry first hatch, they have huge bellies or a yolk sack that they will live on for about 2 days. After that, you can start feeding them infusoria or commercial food for egg layers. 

 You can also use hard-boiled egg yolk. I usually find it best to introduce food with an eyedropper, and simply target the food to where I see the fry. This helps cut down on water fouling, and also gives you a chance to see the fry eating. 

Once the fry are a bit bigger, you can start feeding them killed baby brine shrimp or chopped up frozen food. I never feed fry or juvenile fish live brine shrimp until they are at least ½ inch long.

Nutritional Needs

Overall, Neon Tetras are omnivores. In a natural habitat, they will readily consume meat as well as plant-based foods and algae.

Best Sustenance Food Type: Neon Tetras will do fine with a good quality pellet fish food such as the Hikari brand micro pelllets.

I do not recommend flake foods for this fish because they have very small mouths and can easily choke on larger flakes. If you crumble the flakes up, they can also get stuck in their throats. 

Additional Foods for Optimal Health: Frozen bloodworms, daphnia, and tubfiex worms. They will also readily accept freeze dried tubifex worms. Here again, you may need to chop the food up into smaller pieces, as Neon Tetras can choke on particles that are too big. 

Special Foods and Considerations for Best Color and Growth: Feed live brine shrimp 1 to 2 times per week. They may also enjoy algae wafers or fresh vegetables from time to time. 

When and How often to feed fish based on life cycle: Feed fry and young fish 3 times per day. You can cut back to twice per day when the fish approach 1 year old. If I have females in the tank heavy with eggs, I try to add more frozen food and vegetable material to the tank.

Finicky Fish Management

There are many reasons why Neon Tetras will stop eating. Here are the most common ones and how to manage them. Depending on the situation, just one or all the Tetras may stop eating:

  • Poor Water Quality: Neon Tetras are notoriously susceptible to water quality problems. This includes water chemistry parameters that fall outside the ideal range for their species as well as sudden changes in pH, hardness, nitrates, and nitrites. For pH and hardness, do the adjustments slowly. Nitrates, nitrites, and ammonia you can manage immediately with nitrate/nitrite removing pads and zeolites for ammonia.
  • Bully Fish in the Tank: If you watch carefully, you may notice one fish that makes a point to chase others during feeding time.You can try targeted feeding with a turkey baster (put a little food in the baster, and then fill with aquarium water) where the victim fish is hiding, or partition the bully off to another section of the tank.
  • Injury and Illness: Bacterial, fungal, viral, and parasitic infections can all cause your fish to stop eating. Likewise, fin and body injuries can leave the fish open to pathogens that may not always show up as external infections. You can try using wide range antibiotics for external infections, and then medicated food for internal parasites. 
neon tetra side view

Common Diseases and How to Avoid and Treat Them

I have found Neon Tetras are often more susceptible to ich and body slime than fin fungus and mouth rot. That being said, they are still carriers of all the major opportunistic infections that you would commonly see in an aquarium setting. Therefore, you should always be prepared to diagnose and treat a range of illnesses.

Other than that, there is one disease, called Neon Tetra disease that affects this species as well as other freshwater coldwater and tropical fish. Neon Tetra Disease is caused by an internal parasite, Pleisophora hyphessobryconis. 

Tetras and other fish contract this disease when they consume the flesh of an infected fish or other organism. At this time, there is no cure for this parasite. 

I am a strong believer in using anti-parasite medicated foods on a regular basis, and have never had this disease take root among my Neon Tetras or other susceptible species. Just substitute with medicated anti-parasite food on a weekly basis, or switch immediately to the medicated food if you see changes in fish’s behavior. 

Initial symptoms include restlessness, and a tendency to avoid schooling with other fish. They will also begin to lose coloration and develop lumps and an abnormal increase in spinal curvature.

Finally, the later stages, the fish will fall prey to other pathogens including fin rot, cotton mouth, and just about anything else that happens to be in the tank. 

How to avoid species-specific diseases: The best way to prevent diseases in Neon Tetras is to keep the water quality stable and within the optimal parameters for the species. It is also a good idea to keep these fish in shoals with their own kind. Avoid putting them in with other species that might harass them or stress them. 

Best Antibiotics: Unfortunately, there aren’t a lot of antibiotics that are safe to use on fish that do not have scales. You can try natural formularies that are safe for all fish, however I have found they often aren’t as effective as conventional antibiotics such as methylene blue, formalin, erythromycin, and tetracycline.

Treatments to Avoid: Since Neon Tetras do not have scales, it is best to avoid antibiotics that have a warning against using them with fish that do not have scales. 

Food Recommendations When Sick: use medicated flakes for parasitic, bacterial and fungal infections. If the fish stop eating, try live or frozen foods to see if it will stimulate their appetite.

Hospital Tank or Isolation Within the Community Tank Specifics: Since diseases in tetras often spread quickly to others in the tank, it does not make much sense to remove one sick fish. If others are harassing it, however, you can put it in a partition by itself, and then medicate the entire tank.

3 Interesting Facts About Neon Tetras

  1. The Neon Tetra’s ability to change colors has become a focus in nano particle research that tries to create the same effect in various materials. 
  2. Prior to an outbreak of ich, I often notice that Neon Tetras will nip at the water line more, especially when food is present.
  3. Even though you can’t hear them communicate, when one fish in the school notices something, you can bet the rest will come to investigate. They can be very nosy creatures that will come up to the side of the tank where you are standing and greet you if you wave your fingers at them.

Over the years, I have grown to love the personality and brilliant colors displayed by schools of Neon Tetras in my home aquariums.

I often refer to them as the “make or break” fish for aquarium hobbyists, because Neon Tetra care will challenge you to throw out everything you heard about fish keeping and water changes in favor of water chemistry stability and minimal disruptions.

As you admire their beauty, they will teach you more than any other fish about good aquarium keeping and fish care.

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