A 20-gallon Aquarium is a great option for those who want to keep live plants and freshwater fish species without taking up too much space. However, it’s important to stock the tank wisely to ensure its success.
When choosing the best fish for your 20-gallon tank, it’s not just about knowing which fish grow to an appropriate size. You also need to consider the temperament and needs of any fish you keep and ensure that they are compatibility with each other.
In this guide, National Park Aquarium will introduce you to the 17 best fish species for a 20-gallon tank, including “Schooling Fish, Bottom Dwellers, Centerpiece Fish, Colorful Fish, Unique and Uncommon Fish” that you can keep and provide you with some useful advice on selecting and maximizing the potential of your tank.
Small Schooling Fish for 20 Gallon Tank
If you’re looking for small schooling fish that are beginner-friendly, here are some options that you might want to consider:
- Neon Tetras
- Zebra Danios
1. Neon Tetras
Neon Tetras are small, colorful, and easy to maintain. Their size, peaceful temperament, and preference for schooling make them perfect for a 20-gallon tank, allowing them to thrive and exhibit their beautiful colors.
2. Zebra Danios
Zebra Danios are colorful and beautiful, lively, and easy to care for. They prefer to be in groups, making a 20-gallon tank a suitable habitat that offers enough space for them to school and engage in their active swimming patterns.
These tiny yet vibrant creatures thrive in spacious environments like your 20-gallon tank. Their easy maintenance and adaptability make them a perfect fit. Their fondness for group living adds a lively dynamic to your aquarium.
GloFish are genetically engineered to glow, adding a burst of color to any tank. A 20-gallon tank provides them with enough space to school and exhibit their vibrant colors, making the tank visually captivating.
Bottom Dwellers in 20-Gallon Tank
If you’re looking for bottom-dwelling fish, here are some options that you might want to consider:
- Kuhli Loaches
- Corydoras Catfish
5. Kuhli Loaches
Kuhli Loaches, also known as leopard loach or coolie loach, are small bottom-dwelling eel-like fish fish that live peacefully in freshwater that are known for their peaceful temperament and unique appearance. They belong to the Cobitidae family and are native to Southeast Asia.
6. Corydoras Catfish
Corydoras Catfish are sociable bottom dwellers. A 20-gallon tank is perfect for a small school of these catfish as it provides enough space for them to rummage around the bottom while cohabiting peacefully with other fish species.
Centerpiece Fish for 20 Gallon Tank
A 20-gallon tank is a great size for a home aquarium. If you’re looking for a centerpiece fish to make your tank stand out, there are many options to choose from. Some good options include dwarf gouramis, Striped Panchax, Bolivian Ram, Rosy Barb. All of these species have bright colors and interesting patterns that will bring focus to the center of the tank.
7. Dwarf Gouramis
Dwarf Gouramis are colorful and peaceful. The spaciousness of a 20-gallon tank allows them to comfortably share space with other peaceful fish, and their striking colors add beauty to the tank.
8. Striped Panchax
Striped Panchax is a peaceful surface-dwelling fish that originates from the rivers and streams of India and Sri Lanka. They are perfect for a community tank of 20 gallon, provided that the other fish in there aren’t small enough to fit in its mouth.
9. Bolivian Ram
Bolivian Ram, also known as Mikrogeophagus altispinosus, is a peaceful fish species that pairs well with Rosy Barbs. They are known for their lively yet non-aggressive demeanor, adding variety and a sense of tranquility to 20 gallon aquariums.
10. Rosy Barb
Rosy Barb is a schooling fish that is peaceful and active swimmers. They are perfect for a 20-gallon tank, allowing them to thrive and exhibit their beautiful colors.
Hardy and Low-Maintenance Fish for 20 Gallon Tank
Some hardy and low-maintenance fish that would be great for a 20-gallon tank, include platy and mollies fish.
11. Platy Fish
Platies are compact, resilient fish available in numerous hues. They have a calm demeanor and get along well with other non-aggressive fish. Similar to guppies, they’re an excellent choice for those just starting in the hobby.
12. Mollies Fish
Mollies are relatively easy to care for and peaceful. A 20-gallon tank is their minimum requirement, giving them ample room to swim freely and school with their peers, making for a lively and dynamic tank.
Unique and Uncommon Fish for 20 Gallon Aquarium
If you’re looking for unique fish to add to your 20-gallon aquarium, there are many options to choose from. Some uniqu fish include Scarlet Badis, Sparkling Gourami.
13. Scarlet Badis
Scarlet Badis (Dario dario) is a small freshwater fish species that is native to the tributaries of the Brahmaputra river in West Bengal, India. Scarlet Badis are known for their stunning colors and patterns that cover their bodies.
14. Sparkling Gourami
The Sparkling Gourami (Trichopsis pumila), unique and peaceful, is a small freshwater fish originating from ponds, slow rivers, and rice fields in Southeast Asia. They are known for their iridescent scales and the ability to create a shimmering effect as they move.
7 Best Saltwater Fish for 20-Gallon Tank
Here’s a list of fish you can add to a 20-gallon saltwater tank, especially for beginners.
- Royal Gramma
- Pajama Cardinalfish
- Watchman Goby
- Neon Blue Goby
- Flame Angelfish
15. Clownfish for 20 Gallon Aquarium
Clownfish are popular and charming. Their size, temperament, and diet make them well-suited for a 20-gallon tank, allowing enough space for a pair to thrive and display their vibrant colors.
Firefish are peaceful and vibrant, and a 20-gallon tank gives them sufficient space to live comfortably.
Their diet preference and love for a solitary life make them a good choice for a 20-gallon tank.
17. Royal Gramma
A single Royal Gramma is ideal for a 20-gallon tank. Their size, peaceful nature, and diet make them a suitable choice, allowing enough room for them to display their striking colors.
18. Pajama Cardinalfish
Pajama Cardinalfish are peaceful and easy to care for. The spaciousness of a 20-gallon tank offers them enough room to school and live comfortably.
19. Watchman Goby
Watchman Goby is peaceful and easy to maintain. A 20-gallon tank provides ample space for it to live comfortably, making it a suitable choice for such a tank.
20. Neon Blue Goby
Neon Blue Goby are small, vibrant, and peaceful. Their size, diet, and non-schooling nature make a 20-gallon tank a suitable home for them, giving them ample space to thrive and exhibit their bright colors.
21. Flame Angelfish
A single Flame Angelfish is suitable for a 20-gallon tank. Their size, semi-aggressive temperament, and diet make them a great choice, providing enough space for them to showcase their vibrant colors.
Tips for Choosing Fish for 20-Gallon Aquarium
A 20-gallon aquarium provides ample space for a variety of fish, but it’s essential to choose species that are suitable for this tank size and can coexist harmoniously. Below are some tips and fish recommendations for a 20-gallon aquarium:
Consider the fish’s adult size
Avoid purchasing fish that will grow too large for a 20 gallon tank. Instead, look for species that remain relatively small throughout their lives.
Keep in mind the fish’s temperament
Some fish are peaceful and can coexist with others, while some can be aggressive or territorial. Research the temperaments of your chosen species to ensure they get along.
Factor in swimming space and territory
Mid-water swimmers, bottom-dwellers, and surface swimmers can be combined to utilize different sections of the aquarium.
Think about maintenance and care levels
Some fish have specific water parameters and dietary requirements, so ensure you can provide for their needs.
Some fish might have specific requirements or might not get along with certain other species. It’s always a good idea to check which species can coexist peacefully.
Choosing the fish for 20 gallon tank involves careful consideration of compatibility, size, behavior, and the specific needs of each species. It’s crucial to create a balanced and thriving ecosystem within your aquarium to ensure the health and happiness of your aquatic inhabitants.