Setting up a small aquarium can be an exciting and rewarding experience, but choosing the right fish is crucial to ensure their health and well-being. Not all fish thrive in limited space, so selecting species that can live comfortably in a small tank is essential.
In this article, we will explore the best fish species for small aquariums, their care requirements, and helpful tips to create a healthy aquatic environment.
Understanding Small Aquariums
Small aquariums typically range from 5 to 20 gallons in capacity. These tanks require careful planning, as limited water volume makes maintaining stable water conditions more challenging.
Key Considerations for a Small Aquarium
- Filtration: A good filter is necessary to maintain water quality and remove waste.
- Temperature Control: Some fish require a heater to maintain a stable water temperature.
- Water Changes: Regular partial water changes help keep ammonia and nitrite levels in check.
- Tank Mates: Some fish are peaceful, while others can be territorial or aggressive.
Best Fish for Small Aquariums
1. Betta Fish (Betta splendens)
- Tank Size: 5 gallons or more
- Temperament: Solitary, territorial
- Care Level: Easy
- Water Temperature: 75–80°F (24–27°C)
Betta fish are one of the most popular choices for small aquariums. They come in a variety of colors and have beautiful flowing fins. However, male bettas should be kept alone, as they are territorial and can fight with other bettas. They can live with small, peaceful tank mates like snails and shrimp in a larger tank.
2. Guppies (Poecilia reticulata)
- Tank Size: 10 gallons or more
- Temperament: Peaceful, social
- Care Level: Easy
- Water Temperature: 72–82°F (22–28°C)
Guppies are small, colorful fish that are easy to care for and great for beginners. They are livebearers, meaning they give birth to live fry, so keeping only males is recommended if you don’t want them to breed rapidly.
3. Neon Tetras (Paracheirodon innesi)
- Tank Size: 10 gallons or more
- Temperament: Peaceful, schooling
- Care Level: Moderate
- Water Temperature: 70–81°F (21–27°C)
Neon tetras are small, vibrant fish that do best in groups of at least six. They are active and require a well-planted tank with hiding spots. Their peaceful nature makes them great community fish.
4. Chili Rasboras (Boraras brigittae)
- Tank Size: 5 gallons or more
- Temperament: Peaceful, schooling
- Care Level: Moderate
- Water Temperature: 72–82°F (22–28°C)
These tiny red fish are perfect for nano aquariums. They are shy and should be kept in groups of at least six. A heavily planted tank helps them feel secure.
5. Pygmy Corydoras (Corydoras pygmaeus)
- Tank Size: 10 gallons or more
- Temperament: Peaceful, social
- Care Level: Moderate
- Water Temperature: 72–78°F (22–26°C)
Pygmy corydoras are small bottom-dwelling fish that thrive in groups of five or more. They help keep the tank clean by scavenging leftover food.
6. Endler’s Livebearers (Poecilia wingei)
- Tank Size: 5 gallons or more
- Temperament: Peaceful, active
- Care Level: Easy
- Water Temperature: 72–82°F (22–28°C)
Endler’s livebearers are similar to guppies but smaller. They are hardy, colorful, and easy to care for, making them great for beginners.
7. Scarlet Badis (Dario dario)
- Tank Size: 5 gallons or more
- Temperament: Peaceful, can be territorial
- Care Level: Moderate
- Water Temperature: 72–79°F (22–26°C)
These tiny fish have striking red and blue colors. They prefer a well-planted tank with plenty of hiding spots. Males can be territorial, so keep only one male per tank.
8. Celestial Pearl Danios (Danio margaritatus)
- Tank Size: 10 gallons or more
- Temperament: Peaceful, schooling
- Care Level: Moderate
- Water Temperature: 72–78°F (22–26°C)
Celestial pearl danios, also known as galaxy rasboras, are small, beautiful fish with pearl-like spots. They do best in groups of six or more and prefer a planted aquarium.
9. Pea Puffer (Carinotetraodon travancoricus)
- Tank Size: 10 gallons or more
- Temperament: Semi-aggressive
- Care Level: Moderate
- Water Temperature: 74–82°F (23–28°C)
Pea puffers are tiny but have big personalities. They require live or frozen foods like bloodworms and snails. Due to their aggression, they are best kept alone or in a species-only tank.
10. Kuhli Loach (Pangio kuhlii)
- Tank Size: 15 gallons or more
- Temperament: Peaceful, nocturnal
- Care Level: Moderate
- Water Temperature: 75–86°F (24–30°C)
Kuhli loaches resemble small eels and are excellent bottom-dwellers. They need plenty of hiding places and soft substrate to burrow in.
Tank Setup and Care Tips for Small Aquariums
1. Choose the Right Filter
A sponge filter or a low-flow filter is ideal for small aquariums, as it provides gentle water movement and biological filtration.
2. Maintain Stable Water Conditions
Small tanks can experience rapid changes in temperature and water quality. Perform weekly water changes (20–30%) to keep the water clean.
3. Provide Hiding Spots
Adding live plants, driftwood, or decorations gives fish a sense of security and reduces stress.
4. Avoid Overcrowding
Each fish needs enough space to swim comfortably. Overcrowding leads to poor water quality and stress-related diseases.
5. Use Proper Lighting
LED aquarium lights are ideal for small tanks, especially if you have live plants.
6. Feed High-Quality Food
Offer a variety of foods, such as flakes, pellets, frozen, or live food, depending on the species.
Conclusion
A small aquarium can be a beautiful and enjoyable addition to your home when set up correctly. Choosing fish that thrive in limited space is essential for their well-being. Species like bettas, guppies, neon tetras, and pygmy corydoras are excellent choices for small tanks.
Maintaining a small aquarium requires regular cleaning, stable water conditions, and a well-planned setup. By following these guidelines, you can create a thriving aquatic environment for your fish and enjoy the beauty of a well-maintained tank.
