Lemon Tetra Care: Diet, Tank Mates, Size, Behavior…

Lemon tetras are a lovely freshwater fish that can add a special pinch of color to any aquarium. They’re also quite active and easy to care for.

But for whatever reason, this species is often underrated in the fishkeeping community. We can’t figure it out, because not only do we love them, we know a bunch of other owners who do as well.

If you’re thinking about giving this species a chance, read on to learn everything you need to know about lemon tetra care. You’ll learn about their diet, size, tank mates, behavior, and more!

Species Summary

The lemon tetra (scientific name: Hyphessobrycon pulchripinnis) is a small freshwater fish that can create a big visual impact in your tank. First introduced to the pet trade in the 1930s, these fish are a staple among enthusiasts.

One lemon tetra in a planted tank

Readily available and affordably priced, they’re a good choice for seasoned aquarists and novices alike.

Lemon tetras are native to South America and inhabit parts of the Amazon River. Most often, they can be found dwelling in narrow streams around the Tapajós River basin in Brazil.

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A peaceful and hardy fish, the lemon tetra is one of the easier freshwater species to care for. These fish make great additions to community tanks and can thrive in large groups.


The appearance of the lemon tetra is both familiar and distinct! They have a similar diamond-shaped body like many other types of tetra species. However, lemons tend to be deeper-bodied and more laterally compressed.

Most of the body is semi-transparent. In most specimens, the scales have a pearlescent finish that shines in the light.

The caudal fin is transparent and glass-like. Upon closer inspection, you might see a fine black line around the perimeter of the fin that offers more definition. A similar appearance is found on the pectoral fins.

The dorsal and anal fins are where the fish’s vibrancy is most noticeable! Lemon tetras sport a triangular dorsal fin that’s semi-transparent. Splashes of yellow and black cover the fin and add a touch of color!

Meanwhile, the pointed anal fin is bolder. The front portion of the fin is bright yellow, but a black line borders the rest. In females, this line is pencil-thin. But for males, the black border is thick and prominent.

Hyphessobrycon pulchripinnis looking for food

The appearance of the anal fin is one of the most reliable sexing methods for this fish. Females are usually deeper-bodied, have a compressed dorsal fin, and duller coloration.

Other notable physical characteristics include the presence of an adipose fin and the color of the eyes. The adipose fin is very small. It’s located just before the base of the caudal fin. For most lemon tetras, it’s black and yellow.

Author Note: The eyes of the lemon tetra don’t match the body at all, which makes them stand out! The upper half of the iris is bright red, which deepens and dulls based on the fish’s health.


The average lemon tetra size is somewhere between four and eight years when healthy. While there are plenty of instances when these fish have outlived their expected lifespan, it’s usually a mix of good care and luck.

Like any other fish species, the lemon tetra’s lifespan can suffer dramatically without proper care. In a poorly maintained habitat, these fish can experience stress, disease, and early death.

Average Size

The typical size of a lemon tetra is around two inches in length when fully grown. These fish are quite small, making them convenient no matter how much room you have for them.

Author Note: We like when colorful fish aren’t very large. Their smaller size can create a streaking color effect inside the aquarium!

Lemon Tetra Care

Lemon tetra care is something that we can wholeheartedly recommend to beginners. If you’re looking for a fish species that thrive in captivity, look no further. These gorgeous creatures are hardy and can adapt to a relatively wide range of conditions.

Of course, lemon tetras do have their preferences and certain conditions that are optimal for their health. To help your new fish reach their full potential in your tank, stick to the care guidelines below.

Tank Size

The first thing to consider is the size of your tank. As a small species, you don’t need a massive tank when keeping lemon tetras. However, these fish are very active and require ample space to swim and play.

We recommend starting with a tank size of 20 gallons or more. A 20-gallon tank is sufficient for a small group of six lemon tetras.

Author Note: However, going with a larger tank is never a bad thing! Lemon tetras do best in large shoaling groups, which you can only keep with a tank that holds more volume.

Water Parameters

As always, the best way to keep your lemon tetra healthy is to mimic their natural environment. Fortunately, that shouldn’t be a problem with this species.

These fish come from shallow streams with soft and clean water. While many species from the Amazon require tannin-infused habitats, that’s not the case with lemon tetras. They can do just fine in clear, dechlorinated water.

Overall, lemon tetras are hardy enough to tolerate a generous range of conditions. It’s always good to aim for the middle of these ranges to ensure that there’s some comfortable wiggle room for your fish!

  • Water temperature: 72°F to 82°F
  • pH levels: 5.5 to 8.0 (neutral leaning slightly toward acidic is best)
  • Water hardness: 3 to 20 dGH

To make sure these water parameters stay consistent, you should invest in a water test kit that you can trust. The ability to get quick and accurate readings is a must for any aquarist, and will allow you to make adjustments to the water when needed (before your fish suffer).

What To Put Inside Their Tank

These vibrant freshwater fish helm from densely planted waters in the Amazon. That means a barren and boring tank will not do.

Author Note: In a poorly decorated aquarium, lemon tetras will often lose their color. In some cases, they can even grow anxious and start suffering from disease! Needless to say, spending some time setting up the right environment is paramount!

Aim to create an Amazon biotope. Start with a layer of a fine sand substrate. Then, add driftwood and roots to mimic South American riverbeds.

Once the substrate settles, add a wide variety of live plants. Mix up plant species to achieve a natural forest feel. Utilize ground-cover plants, taller stem plants, and floating plants.

The plants should offer plenty of protection from the light. However, the aquarium should still have ample open space in the middle for swimming. In a densely planted aquarium, these fish can develop rich colors that stand out amongst the greenery!

A lemon tetra swimming inside a freshwater aquarium

Standard filtration systems and lighting will do. Use the outlet of your filter to create moderate water flow in the tank. You can also implement bubble stones for better aeration. Though, they are not necessary if you have a traditional filter.

Potential Diseases

Lemon tetras can suffer from all of the usual freshwater diseases. The most common ailments you need to keep an eye for include ich, bacterial infections, and parasitic infections. These conditions are all contagious and can quickly spread throughout the tank if you’re not careful.

Fortunately, most conditions are treatable with quarantining and over-the-counter medications. Better yet, most diseases are avoidable with proper care!

Stay on top of water conditions and test parameters regularly. You should also make sure that your filter is operating efficiently.

To keep ammonia and nitrate levels down, perform 25 to 50 percent water changes every other week.

Author Note: The cool thing about lemon tetras is that you can use their appearance to gauge their health. If they are suffering from a disease, their intense coloration will start to fade. Color changes are even more apparent if you pay attention to the vibrancy of their red eyes.

Food & Diet

You will have little problems getting lemon tetras to eat! These fish are omnivores and are highly opportunistic when it comes to food. They’ll pretty much eat whatever you provide.

The foundation of their diet should be high-quality dried food. Stick to balanced formulas that offer vitamins and minerals that improve coloration!

You can also improve coloration by keeping the fish’s diet diverse. In addition to dry food, provide occasional live, frozen, or freeze-dried snacks. Lemon tetras are particularly fond of daphnia, brine shrimp, bloodworms, and mosquito larvae.

Feed several small meals throughout the day. Only provide enough food that they can devour in two or three minutes. Keep the diet diverse and your fish will get all the nutrients they need to stay in tip-top shape.

Behavior & Temperament

Overall, the lemon tetra is an easy-going fish that likes to keep the peace. They are active and playful as well!

Like many other tetra species, lemons prefer to stay in groups. Without a group, the fish can become reserved and anxious. This will eventually lead to health problems in the future.

At the very least, keep six fish together. But if you have a large enough tank, aim for at least 12!

Throughout the day, the fish will group up and explore. You may notice some light aggression between males. They can get showy as they try to court females, which results in small battles here and there.

In-fighting is not a major problem and rarely results in significant injury.

Lemon Tetra Tank Mates

A great candidate for community tanks, lemon tetras can get along with a wide variety of tank mates. However, you have to keep things peaceful!

Lemon tetras are small and weak enough to quickly become fish food! Avoid any large and aggressive fish. If you want to keep a multi-species tank, go for similarly sized fish with the same peaceful temperament.

You can try tank mates like:

Author Note: We do know owners who have successfully kept shrimp with lemon tetras, but did so in rather large tanks (over 80 gallons). If you don’t plan on keeping these fish in a large aquarium we recommend avoiding shrimp.


Breeding lemon tetras is an interesting process. They are eager to spawn in the right conditions and can lay a lot of eggs at once! Lemon tetras are community breeders, so you may end up with hundreds or thousands of eggs.

Create a separate breeding tank filled with fine-leaf plants. These tetras are egg-scatterers. But, they don’t show any parental instincts and will try to eat the eggs. Plants provide some protection from hungry adults.

Make sure that your filter has a sponge on it as well to keep any resulting fry safe!

Separate your males and females about a week before you want them to breed. Condition them with live foods to prepare them as well.

When ready, add your males and females to the breeding tank. Slowly raise the temperature to around 80 degrees Fahrenheit.

You’ll know that you triggered spawning when you see the males putting on shows for the females. Once they have performed their rituals, the males and females have an explosive spawning session that results in a cloud of eggs and sperm.

The eggs will fall down towards the bottom of the tank. Once your adults are finished, remove them from the breeding tank to give your baby fish a chance to develop!

The eggs will hatch in about three or four days. After a couple more days, the fry are ready to accept freshly hatched brine shrimp, infusoria, or powdered fish food.

Author Note: Juveniles are usually very dull in coloration. Don’t worry! The intense yellow colors will develop when the fish mature.            


No matter how much experience you have, lemon tetra care shouldn’t be too difficult for you. As long as you follow our recommendations and stay consistent, both you and your fish will be quite happy.

Don’t hesitate to send us a message on social media if you want to provide feedback or have any questions!

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