They are among the most popular aquarium fishes because they are peaceful, colorful, and very easy to care for. They remain small, are able to swim together in groups, and look great in planted tanks. If you are going to keep tetras for the first time, then this guide will provide you with all the simple and useful information on how to take care of them.
1. What Are Tetras?
A small freshwater fish, tetras are primarily found in South America. They are active swimmers and like to stay in a group. Their colours show best when the tank is clean, stable, and has enough plants. Common types include Neon Tetra, Cardinal Tetra, Glowlight Tetra, Ember Tetra, Rummy Nose Tetra, and Black Skirt Tetra.
2. Tank Size & Setup
Even though tetras are small, they need space for swimming. It is recommended to keep them in a minimum 40-50 liter aquarium. They are schooling fish, and you have to keep at least 6 to 10 tetras of the same species. A large school makes them feel safe and look amazing while swimming together.
3. Water Temperature & Quality
Tetras are tropical fish, so they like warm water.
Ideal Temperature: 24–27°C
pH: 6.5–7.4
Water changes: 25–30% weekly
Heater for maintaining a constant temperature. Tetras are sensitive to sudden changes in water conditions, so always strive for stability.
4. Do Tetras Need a Filter?
Yes, a filter is quite important. The tetra needs clean, oxygen-rich water. Use only a soft-flow filter because strong currents make them uncomfortable. You can use sponge filters or low-flow hang-on-back filters.
5. Plants & Decorations
Planted tanks are where tetras will feel the best. They will feel very safe with live plants like Anubias, Java Fern, Amazon Sword, Hygrophila, Vallisneria, and floating plants. They like dark places and places with shade where they can hide and sleep.
6. Tetra Tank Mates
Tetras are peaceful, so their tankmates should be peaceful too. Good tankmates would be:
Guppies
Mollies
Platies
Corydoras
Harlequin Rasboras
Shrimp
Snails
Avoid aggressive fish or large fish that can eat them.
7. Feeding Tetras
Tetras have tiny mouths, therefore they prefer small-sized foods. Feed them:
Micro pellets
Flakes
Frozen bloodworms
Brine shrimp
Daphnia
Feed twice a day, in small quantities. Feed just what they can consume in 1 minute. Overfeeding sickens them and contaminates the tank.
8. Common Tetra Problems
Fin rot – caused by dirty water
Ich (white spots) – caused by stress or sudden temperature drops
Colour fading – happens when they are scared or kept alone
Lethargy – usually due to poor water quality
Most problems go away when the tank is clean, stable, and fish are kept in a proper group.
9. Behaviour of Tetras
Tetras are active swimmers and like to swim right in the middle of the tank. In large groups, they are much more confident and much brighter in color. They are playful, always moving with a school, making the aquarium look alive.
10. Tips for Beginners
Never keep them alone; always in a group.
Keep the tank fully cycled before adding them.
The temperature should be stable.
Add plants for a natural touch.
Do regular water changes.
Use a soft-flow filter.
Avoid noisy or aggressive tankmates.