There are many types of popular small aquarium fish species and sizes to choose from, but if you have a small tank, it’s best to stick with smaller ones, which will be able to adapt well to your environment and won’t outgrow the size of your tank too quickly.
Choosing the right small fish species to put in your aquarium can be an easy process if you know what to look for. Certain small tank fish are more popular than others, and of those popular species, some are more suited to home aquaria than others.
If you have set up an aquarium and are looking to add some aquatic life, there are several popular small aquarium fish that you may want to consider. Many of these fish species don’t grow more than 3 or 4 inches in length, meaning that they work well as individuals or as part of a small community tank.
As you will see below, there are many different varieties of small fish species to choose from and they come in a variety of shapes, colors, and patterns.
In order to find the most popular small aquarium fish species that are also the easiest to care for, you’ll want to consider these 21 small fish species and their needs before picking one out from your local pet store or fish breeder.
Popular Small Aquarium Fish Species
Mickey Mouse Platy Fish (Xiphophorus maculatus)
Mickey Mouse Platy fish is one of the most popular small aquarium fish species. They have been bred to be a variety of colors including black, gold, red, and blue. They are easy to take care of and very hardy for an unfussy fish.
These little guys grow about 2-3 inches in length and can be kept in groups or alone. If you do keep them in a group, there should be at least five or six platies so they feel less lonely. If you want these fish to breed, keep their water temperature between 68°F -72°F and introduce some live plants into the tank. You will need live food as well because these carnivores like to eat insects and insect larvae that come with plants.
Guppy fish (Poecilia reticulata)
The guppy fish is a small freshwater fish that can be found in rivers and streams throughout the world. Guppies are one of the most popular aquarium fish species because they are inexpensive, their size makes them easy to care for, and they come in many different colors.
They have been bred in captivity since 1859, so their genetic variability has increased greatly over time. Wild guppies are only available as adults, but you can find all types of different color variations among captive-bred fish. One interesting fact about guppies is that the male changes color based on social rank, brighter colors indicate higher rank while duller colors indicate lower rank.
Zebra danio (Zebrafish)
The Zebra Danio, also known as the Zebrafish, is one of the most popular and commonly kept aquarium fish species. The zebra danio is originally from India. They are very peaceful and will live in a community aquarium with other small fish species. While they may be aggressive towards their own kind, they get along well with most other tank mates.
These fish grow to an average length of 1-2 inches (2-5 cm). They can reach up to 3.3 inches (8 cm) long, but usually stay closer to 2 inches when they are fully grown. Zebra danios prefer temperatures that range from 76° F – 82° F (24° C – 28° C).
They like living in planted tanks because it gives them places for cover and hiding spots. If there is not enough oxygen in the water for them, these fish may start jumping out of the water or gasping at the surface for air.
Neon Tetra (Paracheirodon innesi)
The Neon Tetra is an easy fish to keep and a great beginner’s choice. They are schooling fish and will do best in a group of at least six. Keep them with other peaceful, small fish that prefer the same water conditions. Avoid keeping them with large or aggressive tank mates as they will get eaten.
The Neon Tetra can grow up to 1 inch long, so make sure you have enough room for your school of six or more.
If you’re looking for something different than what most people get for their first fish, try getting a few Guppies! These colorful little fish come in many different patterns, shapes, and sizes. Some even have markings on their tail like flames! Guppies are very social fish that should be kept in groups of at least three males to one female. Otherwise, they may become stressed and diseased from the lack of females around.
They need clean water without too many waves or currents, but don’t worry; these guys are quite happy just hanging out on plants all day long.
White Cloud Mountain Minnow (Tanichthys albonubes)
The White Cloud Mountain Minnow is a small freshwater fish native to Eastern Asia. These fish can grow up to 12 centimeters in length and have a life span of up to 10 years. They are omnivores and will eat live foods, as well as dried or frozen ones.
This fish does not need any special care or water conditions, making it an ideal beginner’s fish for those looking for something simple. The White Cloud Mountain Minnow is commonly kept in pairs or groups and these fish do best when they are fed several times a day.
The White Cloud Mountain Minnow has been bred with other species to produce different variations that are sought after by aquarium owners all over the world.
Harlequin Rasbora (Trigonostigma heteromorpha)
The Harlequin Rasbora, Trigonostigma heteromorpha, is a small fish that typically reaches just one inch in length. It is often confused with the closely-related Rasbora Heteromorpha.
The Harlequin Rasbora’s coloration can vary from pale green to light pink and it often has black speckles on its body. It usually inhabits still waters of streams and rivers at moderate altitudes in forested regions of Southeast Asia.
It lives among plants such as Nymphaea nouchali and Utricularia spp. where it feeds on insects, zooplankton, crustaceans, tadpoles, and even young frogs.
Serpae Tetra (Hyphessobrycon eques)
The Serpae tetra is a small, peaceful fish that can be kept in a variety of water conditions. The Serpae tetra is an omnivore that will eat both meat and plant-based foods, so it is not necessary to feed them a special diet.
They are generally not aggressive towards other fish, but they will nip at the fins of slow-moving or sleeping fish. The Serpae Tetra requires a 20 gallon aquarium with plenty of cover for hiding places and some driftwood or plants for grazing on algae. You can keep six adult serpaes tetras in a 20 gallon tank as long as you provide plenty of space for each one.
Corydoras panda (Panda Cory)
This small catfish is easy to take care of and makes for a great starter fish. The Panda Cory has a black stripe running from the top of its nose to the base of its tail. It also has a black band that runs across the middle section of its body, as well as two black spots on either side.
These beautiful little creatures have been known to live up to 10 years in captivity if they are taken care of properly. The only downside to this species is it can be difficult to breed them in captivity. The good news is there are plenty more interesting species you can pick up instead!
Glowlight Tetra (Hemigrammus erythrozonus)
The Glowlight Tetra is a beautiful fish that can be found in many pet stores. They are often used to populate the top and middle levels of the aquarium since they are not too big and they stay near the surface.
They can grow up to 2 inches and they like to eat most types of food. Their lifespan is typically 1-3 years but with good care, they can live longer. Another interesting thing about these tetras is that during the breeding season, males have red streaks on their dorsal fins.
Pea Puffer Fish (Carinotetraodon travancoricus)
Also known as dwarf pufferfish, Malabar pufferfish, or pygmy pufferfish, The pea puffer fish is a small, round fish that can be found in the wild on the coastlines of India and Australia. It is also known as the Indian pea puffer or Malayan puffer.
This species of pufferfish is one of the smallest freshwater puffers, growing to about 2 inches in length. The pea puffer is a peaceful fish that should not be kept with aggressive tank mates or other small fishes.
These puffers are prone to an illness called swim bladder disease which will eventually kill them if left untreated. For this reason, it’s important to keep these tanks clean by removing any uneaten food from the tank so it does not rot and release toxic gases into the water.
Tiger Barb Fish (Puntigrus tetrazona)
The Tiger Barb is a schooling species and prefers to be in groups of six or more. It can grow up to 12-inches long with bold stripes on its body, hence the name Tiger. They are carnivorous and will eat any small live food offered, such as bloodworms, brine shrimp, and tubifex worms.
However, they should not be fed crustaceans such as crab legs, shrimp, and lobster because these can cause health problems. They also enjoy eating plants so it’s best to add them into their habitat to provide cover and make them feel safe.
Swordtail Fish (Xiphophorus helleri)
The swordtail fish is a native of Mexico and Central America. This freshwater species can grow up to 12 inches long and live 10 years or more with proper care. Swordtails are kept in community tanks, but they should be the last fish added because they are very active and will likely chase other fish away.
As one of the most popular small aquarium fish species, it’s no wonder that the swordtail has been bred into a wide range of colors with variations in fin shape. Males have longer, pointed dorsal fins while females have shorter, rounded ones.
Both sexes are marked with vertical bars which fade as they age. When breeding them, keep the water temperature below 76 degrees Fahrenheit to avoid inducing spawning at an undesired time.
German Blue Ram Cichlid (Mikrogeophagus ramirezi)
The German Blue Ram Cichlid is a popular fish among aquarists because it’s hardy and easy to care for. The German Blue Ram Cichlid also gets along well with other tank mates. These fish will not get as large as some of the other cichlids, so they are good for smaller tanks.
They have a dark blue body with light blue stripes on their back, and a black spot on their nose. Male German Blues usually grow larger than females do. Males typically grow up to 6 inches in length while females generally only grow up to 4 inches in length.
They should be kept in water that has a pH level between 7 and 8 and dH levels between 3-8. These fish should be fed once or twice per day with food that is appropriate for them depending on what size they are at the time being fed; this could include live, frozen, freeze-dried or flake food sources.
Buenos Aires Tetra (Hyphessobrycon anisitsi)
Buenos Aires Tetras are a popular and hardy aquarium fish. They originate from the Rio de la Plata basin, which includes Argentina and Uruguay, in South America. Buenos Aires tetras are a peaceful species that will coexist well with other small fishes.
These tetras prefer to swim near the surface of the water, where they can come into contact with the air for oxygen intake. However, they can often be found swimming at various depths of the tank as well.
Their natural habitat is among plants or roots. As such, they should be provided with plenty of space to swim around and hide among these structures. The Buenos Aires Tetra is an omnivorous fish that consumes both plant matter and meat.
Trichogaster lalius (Dwarf Gourami)
Trichogaster lalius, also known as the Dwarf Gourami, is one of the most popular small aquarium fish species. They are relatively easy to care for and can live in a tank as small as 10 gallons. As long as you keep their tank clean, feed them three times a day and provide them with places to hide from other predatory fish, they will be happy for many years to come.
When setting up a tank for Dwarf Gouramis make sure that you have rocks, plants, and plenty of places where they can feel safe. It is recommended that when keeping these fish the filter should not produce too much suction which might suck them up or dry out their fins. In addition to this make sure that there are no sharp objects near the water surface as this could injure them or kill them by chopping off their gills.
Gold (Chinese) Barb (Barbodes semifasciolatus)
The gold barb, or as it is also called, the Chinese barbel, is a small schooling fish that prefers living in schools of five or more. When kept with other species of similar size, they are generally peaceful and will not harass any other fish.
They prefer to be fed small live foods such as brine shrimp, blood worms, and daphnia. However, their diet can also consist of some finely chopped frozen food. Gold barbs can grow to 12 cm long when fully grown.
These tiny beauties should only be placed in tanks that have no less than 10 gallons of water per gold barb. To keep them happy, use soft water with a pH level between 6.8-7.2, and do not add ammonia or nitrites into the water.
In addition to being very beautiful, these little guys make an excellent addition to your aquarium because they help control algae growth by eating it up!
Siamese fighting fish (Betta splendens)
Siamese fighting fish are colorful, social fish that enjoy being kept in pairs. They require an aquarium with a shallow depth and plenty of water-surface area for swimming. They should be fed high-quality flake food or pellet, as well as occasional live food.
They require an aquarium with a shallow depth and plenty of water-surface area for swimming. They should be fed high-quality flake food or pellet, as well as occasional live food. It is also important to maintain their aquarium with regular water changes to prevent bacteria from accumulating in the tank and harming the fish.
The male’s long tail may become tangled with the female’s; during this time both sexes refrain from eating, so it is important to feed them enough so they don’t starve while they mate.
The male’s long tail may become tangled with the female’s; during this time both sexes refrain from eating, so it is important to feed them enough so they don’t starve while they mate.
Hachetfish (Gasteropelecidae)
The Hachetfish is a small fish that can reach up to 5 inches in length. The head of this species is shaped like a hatchet which inspired its name. They are found in the coastal regions of the eastern Pacific Ocean and the Gulf of California. Hachetfish prefers living at rocky or sandy bottoms where there are plenty of places for them to hide from predators.
They feed on zooplankton, crustaceans, and other small invertebrates in the wild. However, they are not considered an important food source for humans due to their scarcity. If you want one as your pet it is best to keep it in a community tank with a sand or mud bottom so they have plenty of places to hide and feel safe.
Congo Tetra (Phenacogrammus interruptus)
The Congo Tetra is a small, inexpensive, and peaceful fish species with an iridescent blue sheen. The Congo Tetra requires at least five gallons of water and should not be kept in tanks smaller than 30 gallons. This tank-mate is compatible with many other aquarium species including goldfish, guppies, mollies, platys, and swordtails.
Congo tetras are omnivores that will eat a variety of both meaty and plant-based foods. A diet high in vegetable matter such as lettuce, spinach, cucumber slices, zucchini slices, and peas is recommended for this species. Many pet stores sell the same fish under the common name fire tetra.
The Beacon is a small schooling fish that does well in a community tank. They are brightly colored, yet shy and peaceful. They do best in tanks with live plants as they like to hide among the foliage and will not venture out much if there is no hiding place nearby.
They need to be kept in groups of 6 or more, preferably 10 or more to ensure they feel safe and secure. They have an average lifespan of 3-5 years, but some have been known to live up to 7 years when cared for properly.
They reach 1.5 inches long. Their water needs to be clean, so frequent water changes should occur between 25% – 50%. If you plan on breeding them, it is recommended you keep them in a separate breeding aquarium. They are omnivorous and require both vegetable matter and meaty foods.
Black Phantom Tetra (Hyphessobrycon megalopterus)
The black phantom tetra is one of the most popular species of fish in the aquarium trade. They are native to the Amazon River basin in South America, but their natural habitat has been heavily impacted by pollution and overfishing. Black phantom tetras may live up to 10 years and reach about 4 inches.
They have a reputation for being easy to care for, though they will eat anything that fits into their mouth, so be sure to provide a varied diet. Be cautious when placing them with other small fish because they can be quite territorial.
Keeping this in mind, it’s best to keep them with similar-sized fish or larger ones that won’t mind the occasional skirmish. In an overcrowded tank, they may show aggressive behavior toward each other.
They are great community tanks as long as there aren’t too many of these fish crammed together at once.
Black Ruby Barb (Pethia nigrofasciata)
Also known as Purplehead barb, this small fish is not a true barb but rather a member of the Cyprinidae family, more specifically the Pethia genus. They are native to India and Pakistan and can be found in rivers that flow into the Bay of Bengal.
Black Ruby Barb’s have a black body with red fins. They prefer water temperatures of 78-86 degrees Fahrenheit, which is around 25 to 30 degrees Celsius.
In captivity, they are mostly found in freshwater aquariums where they feed on live worms or insect larvae.
It is suggested to keep them in groups of 3 or more because they do not like to feel lonely. When kept as a single specimen, it will become very shy and hide from other inhabitants of the tank. Their lifespan ranges between 5 to 8 years.
