10 Top Fish for Nano Aquariums: Small-Space Fishkeeping
Nano aquariums-shortly, compact fish tanks generally under 10 gallons-are best suited to the aquatic lover who has little space but still wants the beauty of fish. Nano aquariums are ideal for a small house, office, or apartment and offer a beautiful, manageable introduction to fishkeeping. But not all fish are designed to remain in a nano tank; therefore, selecting species that not only tolerate but also thrive in small spaces is crucial. Here are some of the best fish for nano tanks along with tips on how to keep them happy and healthy.
1. Betta Fish (Betta splendens)
One of the most popular options for nano aquariums is Betta fish due to their gorgeous colors and individual character as well as their ability to thrive in smaller tanks. In fact, these fish can thrive well in a 3-gallon tank, though a 5-gallon tank is better. They are relatively low maintenance but are best kept alone, as male Bettas are known to be aggressive toward other fish, particularly other Bettas.
Care Tip: Tank lid as they jump and gentle filtration for a clean, but not riotous flow of water.
2. Chili Rasbora (Boraras brigittae)
Chili Rasboras are extremely colorful, tiny fish that excel in nano tanks. They cap out at only slightly above 0.8 inches in length, so 5 gallons is a great tank size. The bright red and black color does very well in a plant-only tank. Chili Rasboras are non-aggressive and should be kept in schools of six or more.
Care Tip: They prefer soft, slightly acidic water and thrive best in planted tanks with minimal water movement.
3. Neon Tetra (Paracheirodon innesi)
One of the classic choices is Neon Tetras, which shine with vibrant blue and red stripes on small, peaceful fish in any nano tank. They can grow up to about 1.5 inches, so they should be kept in a comfortable 10-gallon tank, though they thrive much better in larger groups of at least five.
Care Tip: Neon Tetras prefer slightly acidic water and dim lighting, so floating plants help create an ideal environment for them.
4. Pygmy Corydoras (Corydoras pygmaeus)
Pygmy Corydoras are small, lively catfish. They reach an inch in length and will be happy to fill out any peaceful shoal while also helping to keep the bottom of the tank clean, therefore making them perform admirably at water quality.
Care Tip: They need a substrate such as sand or smooth gravel and should be protected from rubbing their sensitive barbels.
5. Celestial Pearl Danio
The Celestial Pearl Danios, also referred to as Galaxy Rasboras, are wonderful for the nano tank. The small fish have a size of one inch long and prefer to be in schools of five or more. What make these gentle fish make superb inhabitants of a nano tank are its magnificent spotted coloration, which will come out brightest when they feel safe with some hiding places among plants.
Care Tip: Maintain stable water parameters with minimal fluctuations, as it is sensitive to any change in water quality.
6. Endler's Livebearer (Poecilia wingei)
Endler’s Livebearers – These are colourful, robust fish which resemble Guppies but remain much smaller. The males are in particular beautifully coloured, both in pattern and coloration, and will do well in small tanks. They breed easily, so a small group can quickly multiply. Thus it is very important to have a plan of management for your tank.
Care Tip: If you don’t want your nano tank to get overwhelmed with the babies, separate the male and female.
7. Scarlet Badis (Dario dario)
With their deep red color and very small size, Scarlet Badis are excellent for nano aquariums. They grow to be about 0.8 inches long, and they are best kept in a peaceful environment, especially alone or in pairs. They will display intense coloration when courting, making it quite a delightful time for the aquarist.
Care Tip: Scarlet Badis are fussy eaters and seem to prefer live or frozen food rather than pellets or flakes.
8. Pea Puffer (Carinotetraodon travancoricus)
The Pea Puffers are one of the most amusing fish because they are interactive and inquisitive. That would make them a very interesting choice for nano aquariums. Still, these little fish only grow to about 1 inch in size and thrive well in a 5-gallon aquarium, though they will naturally be territorial, making a single Pea Puffer per tank ideal unless it’s a larger nano setup.
Care Tip: Pea Puffers can become bored with their food and need some variety in the diet, including live or frozen foods such as bloodworms and brine shrimp.
9. Dwarf Gourami (Trichogaster lalius)
Dwarf Gouramis are a vibrant blue and red, and are one of the slightly larger species that still do well in a 10-gallon nano tank. They are generally peaceful but the males do have a bit of a territorial streak. Dwarf Gouramis do best in a planted environment with plenty of hiding places.
Aquarium Tip: Maintain only one male Dwarf Gourami in a tank, as males fight aggressively with other males.
10. Guppy (Poecilia reticulata)
Guppies tend to be popular for their easy care and colorful appearance as well as their active personalities. They do very well in nano tanks of at least 5 gallons, but like all of Endler’s Livebearers, they can breed prolifically, so managing population is important. Guppies are excellent in a group aquarium as they add lively energy to the environment.
Care Tip:Â Separate males and females or prepare for fry if you have a mixed group in the tank.
FAQs (frequently-asked questions)
The number of fish will depend on the type and size of tank. However, a good rule of thumb is to consider one inch of fish per every gallon of water. As long as you are not overcrowding you are less likely to have bad water quality and stressed fish, so just make sure to be conscious of the stocking levels.
Yes, filtration will keep the water clean and well-oxygenated. The filtering of a nano tank needs to be gentle because there is a necessity to avoid the strong currents that can stress out the fish.
For nano tanks, regular water change should be maintained because accumulation of waste might be rapid. Change 20–30% of the water weekly as well as monitor the water parameters of your fish while making sure they stay healthy.
Yes. Plants are incredibly helpful in nano tanks; they improve water quality, reduce fish stress, and enhance the view. Low-light species, such as Java moss and Anubias, are very suitable in a small tank.
