Choosing the right fish species is essential when setting up a small aquarium. Fish that thrive in small tanks tend to be peaceful, adaptable, and relatively low-maintenance. However, selecting the best species is not only about picking the most attractive fish; it’s also about ensuring compatibility with your tank size, water conditions, and the other fish in the tank.
In this article, we will explore some of the best fish species for small aquariums, focusing on species that do well in compact environments and are relatively easy to care for.
1. Factors to Consider When Choosing Fish for Small Tanks
Before diving into specific fish species, it’s important to understand the factors that determine whether a fish is a good fit for a small aquarium. Here are some considerations to keep in mind:
1. Tank Size
Small aquariums generally refer to tanks between 5 to 20 gallons. Fish that are suited for small tanks should not grow too large, as they may become stressed in confined spaces. Also, certain fish species have specific swimming and territorial needs that require more space.
2. Fish Compatibility
Some fish species are more aggressive or territorial, which can lead to conflict in a small tank. It’s essential to select fish that are peaceful and can coexist with other tank mates without causing stress or harm. In small tanks, keeping aggressive fish together can lead to territorial disputes and overcrowding.
3. Temperature and Water Conditions
Different species of fish have different temperature and water condition requirements. Before choosing fish, make sure the species you select are compatible with each other’s water temperature, pH levels, and hardness.
4. Fish Activity Level
Fish activity varies from species to species. Some fish are more active and will need space to swim freely, while others are more sedentary and prefer to remain at the bottom of the tank or in hiding. For small tanks, it’s often a good idea to mix active fish with more docile ones.
2. Best Fish Species for Small Aquariums
Now that we’ve covered some of the factors to consider when choosing fish, here are the best species for small aquariums that meet the criteria of size, temperament, and ease of care.
1. Betta Fish (Betta splendens)
Betta fish, also known as Siamese fighting fish, are a favorite among aquarium enthusiasts due to their vibrant colors, ease of care, and compact size. Male bettas, in particular, are known for their stunning, flowing fins and aggressive territorial behavior, but they can thrive in a small aquarium as long as they are kept alone.
Why They’re Ideal for Small Aquariums:
- Tank size: Betta fish can live happily in tanks as small as 5 gallons, although a 10-gallon tank provides more space.
- Temperament: Male bettas are solitary, which makes them ideal for small tanks. Avoid keeping more than one male betta in the same tank, as they can be highly territorial.
- Water conditions: Bettas are hardy and can tolerate a range of temperatures but prefer water between 75°F and 80°F (24°C to 27°C).
Care Tips:
- Provide a lid for the tank, as bettas can jump.
- Keep the tank free of sharp decorations that may tear their delicate fins.
2. Guppies (Poecilia reticulata)
Guppies are small, peaceful, and colorful fish that do well in groups, making them ideal for community tanks in small aquariums. They are especially well-suited for beginners due to their adaptability, hardiness, and relatively low-maintenance care.
Why They’re Ideal for Small Aquariums:
- Tank size: Guppies thrive in aquariums as small as 5 gallons, though they do better in larger groups in tanks of 10 gallons or more.
- Temperament: Guppies are social fish and prefer to be kept in schools of at least 5–6 individuals. Their peaceful nature makes them suitable for community tanks.
- Water conditions: Guppies are adaptable to a variety of water parameters but prefer water temperatures between 74°F and 82°F (23°C to 28°C).
Care Tips:
- Keep guppies with other peaceful fish that won’t compete for food or territory.
- If you have both male and female guppies, be prepared for babies, as they breed readily.
3. Neon Tetras (Paracheirodon innesi)
Neon tetras are small, striking fish known for their vivid blue and red coloration. They are peaceful, active swimmers that do well in small groups and are perfect for aquariums with limited space.
Why They’re Ideal for Small Aquariums:
- Tank size: Neon tetras thrive in tanks as small as 5 gallons, but they are happiest in groups and do better in larger tanks with a minimum of 10 gallons.
- Temperament: Neon tetras are peaceful, schooling fish that get along well with other species. Keeping them in groups of 6 or more will ensure they feel secure and minimize stress.
- Water conditions: Neon tetras prefer slightly acidic to neutral water with temperatures between 70°F and 81°F (21°C to 27°C).
Care Tips:
- Ensure the tank has plenty of plants and hiding spots for the tetras to feel secure.
- Provide a gentle filter to avoid strong currents that may stress them.
4. Corydoras Catfish (Corydoras spp.)
Corydoras catfish are small, bottom-dwelling fish that are perfect for small tanks due to their peaceful nature and small size. These fish are known for their cute, armored bodies and are often used in aquariums to help clean up leftover food from the substrate.
Why They’re Ideal for Small Aquariums:
- Tank size: Corydoras catfish do well in aquariums as small as 10 gallons, though they are best kept in groups of at least 3–5 fish.
- Temperament: Corydoras are peaceful, social fish that get along with most other species. They tend to stay near the bottom of the tank, so they won’t compete for space with other fish.
- Water conditions: These catfish prefer temperatures between 72°F and 78°F (22°C to 26°C) and slightly acidic water.
Care Tips:
- Corydoras are bottom-dwellers, so provide a soft substrate like sand or fine gravel to prevent injury to their delicate barbels.
- They are sensitive to poor water quality, so regular water changes and good filtration are important.
5. Cherry Shrimp (Neocaridina davidi)
While not technically a fish, cherry shrimp are a great addition to small aquariums, particularly for nano tanks. These tiny, colorful creatures are excellent at cleaning up algae and detritus in the tank and can coexist peacefully with many fish species.
Why They’re Ideal for Small Aquariums:
- Tank size: Cherry shrimp thrive in tanks as small as 5 gallons. However, they do better in larger tanks with plenty of hiding spots.
- Temperament: They are peaceful creatures and won’t bother other fish or tank mates. However, be mindful of larger, predatory fish that may try to eat them.
- Water conditions: Cherry shrimp prefer water temperatures between 65°F and 80°F (18°C to 27°C) and slightly alkaline water with a pH of around 7.0–8.0.
Care Tips:
- Provide plenty of plants or hiding places to give shrimp a sense of security.
- Avoid using copper-based medications in the tank, as copper is toxic to shrimp.
6. Zebra Danios (Danio rerio)
Zebra danios are small, active fish that are perfect for small tanks. Known for their distinctive blue-and-white striped pattern, they are hardy and adaptable, making them an excellent choice for beginners.
Why They’re Ideal for Small Aquariums:
- Tank size: Zebra danios do well in tanks as small as 5 gallons, although they are happiest in schools of 5 or more individuals.
- Temperament: Zebra danios are peaceful, active fish that are great for community tanks. They are particularly good with other small, non-aggressive fish.
- Water conditions: Zebra danios are adaptable and can tolerate a wide range of water temperatures, from 64°F to 75°F (18°C to 24°C).
Care Tips:
- Provide a well-planted tank with some open swimming space.
- Keep the water quality high to prevent stress and disease.
7. White Cloud Mountain Minnows (Tanichthys albonubes)
White cloud mountain minnows are small, hardy fish that thrive in cooler temperatures. These fish are perfect for small aquariums, especially if you don’t want to keep tropical fish.
Why They’re Ideal for Small Aquariums:
- Tank size: They do well in tanks as small as 5 gallons.
- Temperament: These minnows are peaceful and get along well with other small, non-aggressive fish.
- Water conditions: They thrive in cooler water temperatures, ranging from 60°F to 72°F (15°C to 22°C), making them ideal for unheated tanks.
Care Tips:
- Provide a tank with plenty of plants and open swimming space.
- Keep them in groups of 5 or more to reduce stress and encourage natural schooling behavior.
3. Conclusion
When choosing fish for small aquariums, it’s important to select species that are not only visually appealing but also compatible with the limited space and water conditions. Fish such as bettas, guppies, neon tetras, and zebra danios are ideal for small tanks, as they are small, peaceful, and relatively easy to care for.
By understanding the specific needs of each species and carefully selecting compatible tank mates, you can create a thriving aquatic environment in your small aquarium. Whether you’re a beginner or an experienced fishkeeper, the right fish will bring your small tank to life and create a beautiful, harmonious underwater world.
