Overview
The lemon tetra is a small, flat-bodied fish from the slow, shady streams that feed the Amazon River in Brazil. Its body is mostly silvery and almost see-through, but along the top and in the fins you can spot bright lemon-yellow color and a splash of black. The more relaxed and healthy the fish is, the brighter that yellow becomes, so a glowing lemon tetra is a happy lemon tetra.
These fish are true schoolers, which means they feel safe only when they travel in a crowd. Kept alone or in tiny numbers they turn pale and hide, but in a group of six or more they swim out in the open and show off their color. That makes them a favorite for peaceful community tanks where lots of gentle fish live together.
| Care level | Easy |
| Adult size | 1.75 in (4.5 cm) |
| Lifespan | 6-8 years |
| Temperament | Peaceful |
| Min. tank | 20 gallons (76 L) |
| Temperature | 72-82 F (22-28 C) |
| pH | 5.5-7.5 |
| Diet | Omnivore |
| Schooling | Yes, keep 6 or more |
Where they come from
Lemon tetras live in the clear and blackwater streams of the central Amazon basin. These waters are soft and a little acidic, stained the color of weak tea by fallen leaves. The shade from overhanging trees and floating plants makes the perfect calm home for a small schooling fish.
How to spot one
Look for a diamond-shaped, silvery body with a bright yellow front edge on the fins and a bold black stripe in the top fin. Their eyes often have a flash of red at the top. Males tend to show a wider black band on the anal fin than females.
Life in a school
In a big enough group, lemon tetras spread out and swim in the middle of the tank all day. They gently chase and display to each other, which is normal play and helps them stay bright. A lonely tetra gets stressed, so numbers really matter for this species.
What they eat
Lemon tetras are omnivores that nibble tiny insects, larvae, and bits of plants in the wild. In an aquarium they happily eat flake food, small pellets, and treats like frozen daphnia or bloodworms. A mix of foods keeps their color strong.
Good tank mates
Because they are so peaceful, lemon tetras fit well with other calm fish of a similar size, like corydoras catfish, other small tetras, and gentle rasboras. Avoid big or nippy fish that might bully or eat them.
Fun facts
- The name pulchripinnis means beautiful fin in Latin, a nod to their yellow-trimmed fins.
- A stressed or lonely lemon tetra fades to pale silver, so their color is like a mood ring.
- They have been kept by aquarium hobbyists since the 1930s.
- Wild lemon tetras live in soft, tea-colored blackwater streams.
- Males show a thicker black band on the fin near their tail than females do.
Frequently asked questions
How many lemon tetras should I keep together?
At least six, and more is even better. In a bigger group they feel safe, stay brightly colored, and swim out in the open where you can enjoy them.
Are lemon tetras hard to care for?
No, they are one of the easier tetras. As long as the water is clean, warm, and not too hard, they are hardy and forgiving, which makes them great for newer fishkeepers.
Will they bother other fish?
Not really. They are peaceful and spend their energy displaying to each other. Just keep them with other calm fish of a similar size.
Why did my lemon tetra lose its yellow color?
Fading usually means stress, often from being in too small a group, dirty water, or a scary tank mate. Fix the cause and the sunny yellow usually returns.
