Ideal rainbow fish tankmates would be fish of a similar size or smaller. They are one of the most popular freshwater tropical fish species, and with good reason – they’re beautiful, relatively easy to care for, and compatible with many other types of tropical freshwater fish!
That being said, most rainbow fish require specific water parameters and should never be mixed with other species of rainbow fish (except those from the same region). Luckily, there are many other tropical fish that make great tankmates for rainbow fish!
In order to keep your rainbow fish happy and healthy, it’s important to provide them with the right environment, including friends that can keep them company and not fight over the same food and territory.
If you’re in the market for more fish to put into your already thriving tank, it can be hard to know what kinds of fish will get along with your current aquarium mates and which will cause problems as they try to establish dominance.
The most common mistake people make when they set up their tanks, especially if they’re new to the hobby, is not thinking about the personalities of all the fish and how they might react to each other – but luckily, we’ve got you covered!
We’ve compiled this list of 18 best rainbow fish tankmates along with photos and care information to help you make the best choice possible! Enjoy!
Rainbow fish tankmates
Glowlight Tetra (Hemigrammus erythrozonus)
The Glowlight Tetra is a small schooling fish that can be found in parts of South America. They are not the most colorful of rainbow fish, but they do have a distinct red glow to their body when viewed under UV light.
The Glowlight Tetra prefers to live with other small, non-aggressive species such as Otocinclus catfish or Bristlenose Pleco. They should be kept in groups of at least 6 for optimum health and happiness.
These tetras get along well with many other species and would make a great addition to any community tank.
Guppies (Poecilia reticulata)
Guppies are a perfect starter fish for anyone interested in keeping a freshwater aquarium. They are small, come in many colors, and have a reputation for being easy to care for.
Guppies only grow to about 3 inches (7.5 cm), so they will not take up too much space in your tank or outgrow their home too quickly. They also prefer water temperatures between 74-82 degrees Fahrenheit (23 to 28 degrees Celsius).
You can keep them with other small species of fish as long as you provide enough hiding places for them to escape from predators and live comfortably.
Remember that guppies reproduce very quickly if you allow them to mate, so make sure you get both males and females if you want guppies to reproduce in your tank!
Sailfin Molly (Poecilia latipinna)
Sailfin Mollies are one of the most popular fish in the aquarium trade and for good reason. They come in a wide variety of colors, including blue, yellow, green, red, and brown.
Sailfin Mollies are peaceful schooling fish that can be kept with other species in a community tank.
Other than their coloration, Sailfin Mollies are similar to Platy fish because they have long fins and swim like miniature sailboats. They should not be kept with aggressive or territorial fish because these attributes make them easy targets.
Although this species is generally very hardy, it is prone to diseases such as ich (Ichthyophthirius multifiliis) and parasites like anchor worms (Lernaea).
You will want to quarantine your new Sailfin Molly before adding it to your established aquarium so that you can monitor its health during this time.
Swordtail fish (Xiphophorous hellerii)
Swordtail fish are freshwater fish native to Central America. They have a black or olive body with vertical stripes and can grow up to 8 inches long.
They are one of the best rainbow fish tank mates because they are fairly easy to care for and they eat most foods that you feed them. They also live in planted tanks, which will provide a healthy habitat for your other rainbow fish.
Wagtail Platy (Xiphophorus maculatus)
The Wagtail Platy is a small fish that is bred in captivity and generally found in pet stores. It has a body shape similar to the Swordtail, but much smaller. The wagtail platy has an olive-colored body with black stripes that run the length of its body.
They also have bright red fins and dark green markings on their head. These colors come from certain types of dyes injected into them during their larval stage. These colors will not fade away over time because they are part of the cells themselves.
Pictus Catfish (Pimelodus pictus)
Also known as Spotted Pimelodus, the Pictus Catfish is a great, low-maintenance addition to any freshwater tank. They are found in the Amazon and Orinoco river basins of South America.
They have a life span of up to 15 years and can grow up to 12 inches long, making them one of the larger species in this list. They are mainly bottom feeders, eating most types of plants and algae.
They will even eat small invertebrates like worms. Be sure not to keep more than one male per tank because they will fight with each other constantly. They are also prone to infection so do your best to provide good water quality and add live plants if possible.
Zebra Danio (Danio rerio)
The Zebra Danio is a small freshwater fish native to India. The males grow to about 2 inches, while females only reach 1 inch. These fish are great for beginners because they are very hardy and will live in both cold and warm water.
They also come in many different colors, which makes them appealing to fish lovers who want something unique. However, the downside of this fish is that they have been bred to have less color variation than other zebrafish species, so if you’re looking for more vibrant coloration, you might want to look elsewhere.
Regardless of their lack of variety in coloration, these fish are still a good choice as rainbow tank mates because they thrive at temperatures between 65-82 degrees Fahrenheit.
Mosquito Rasbora (Boraras brigittae)
Mosquito Rasbora, also known as Chilli rasbora, are one of the best rainbow fish tankmates because they eat mosquito larvae and other little pests that might be growing in your tank.
They also like to swim in small groups, so you could get two or three for your tank.
Mosquito Rasbora are very peaceful and won’t bother any other fish you have in the tank.
They only grow to about 1 inch long, so they won’t need as much space as some other aquarium fish do. The male is slimmer than the female and has a longer anal fin than she does. Male mosquitoes don’t even start showing colors until they’re at least 8-10 months old!
They can live from 3 to 5 years if kept in an appropriate tank environment.
Mosquitofish should not be kept with bottom dwellers such as loaches, catfish or goldfish because they will nip at their fins. They can live alone or with other mosquito rasboras of both sexes without aggression.
Denison Barb Fish (Puntius Denisonii)
Also known as Denison’s barb, Miss Kerala, red-line torpedo barb, Roseline shark, or Sahyadria denisonii, The Denison Barb fish is a brightly colored fish that is often compared to the neon tetra.
They are very timid and will do best when kept in shoals of at least 6-8, but can be kept with other shoals or species as long as they are in larger groups. This small schooling fish is peaceful, hardy, and easy to care for making it one of the best rainbow tank mates for beginners.
They also require minimal work on your part since these only need 10-15% water changes once per month.
Denison Barbs are also tolerant of most water conditions from acidic pH levels to low water hardness so you don’t have to worry about changing out the water regularly if you have them in your tank!
Rainbow Kribensis Cichlid (Pelvicachromis pulcher)
The rainbow Kribensis cichlid, also known as the Pelvicachromis pulcher or simply Rainbow kribs, is a species of cichlid from Africa. It has a dark blue to green body with orange, yellow and red bands on its scales.
The males can be identified by their larger size and brighter colors than females. They typically grow to be 8-10 cm in length. These fish are considered an African Cichlid due to them being found exclusively in Africa.
Their diet consists mainly of small insects and crustaceans that they sift through sand or other substrates for. These fish should not be kept with other African Cichlids since they will hybridize very easily with each other.
The angelfish is a freshwater fish that can grow up to 8 inches in length. They are one of the most popular aquarium fish and can be found in many pet stores. Angelfish come from South America, but you will see them in North American stores as well.
The angelfish have long, flowing fins that make it a stunning addition to any tank. Angelfish are an excellent choice for a beginner because they are hardy and easy to care for.
Make sure that your angelfish only has enough room to swim around without bumping into other fish. It is also important not to put your angelfish in too small of a tank. Finally, provide the angel with plenty of live or fake plants to help make them feel safe and secure.
Dwarf Gourami (Trichogaster lalius)
The Dwarf Gourami is a freshwater fish from Southeast Asia. They have a lifespan of 10 to 12 years and grow up to three inches in length. The most popular color variety is orange, but they are also available in red and blue. Females are sometimes more colorful than males, but the difference is not always clear.
The Dwarf Gourami needs plenty of hiding places among rocks or plants for security as well as swimming space. In addition, they require a tank that holds at least 20 gallons and an appropriate filter.
A single pair can be housed in this type of tank as long as there are some open spaces where other fish can swim by. When possible, it’s best to keep these types of rainbow fish with one male per female since dwarf gouramis can be aggressive with each other if they’re too close together.
Clown Loach (Chromobotia macracanthus)
Clown Loach are a good choice for rainbow fish tankmates. They are peaceful and can be kept with other fish that enjoy the same water conditions. They can grow to 12 inches in length, but don’t worry if your clown loach outgrows the tank because they are great swimmers and will be just fine in a larger aquarium.
Clown loaches prefer plant cover as it provides them with a place to hide if they feel threatened or scared. Provide plenty of plants to keep them happy. It’s best not to put plants on the bottom of their habitat because they like stirring up substrate while they search for food.
Zebra Pleco (Hypancistrus zebra L046)
Zebra Pleco are common in the pet trade and would make a great addition to any community tank. They are moderately sized at about three inches but can grow up to four.
The Zebra Pleco is omnivorous and prefers both meaty foods, like worms, shrimp, and bloodworms as well as veggies like cucumber and zucchini. They are easy to feed because they will eat just about anything you put in front of them.
However, it’s important not to overfeed these guys so that there isn’t excess waste in your tank. These fish are also relatively slow growers and may live for 20 years if cared for properly.
Peacock Gudgeon (Tateurndina ocellicauda)
The peacock gudgeon can be a great addition to a tank as they are peaceful and won’t nip the fins of other fish. They have an elongated body that is covered in iridescent scales.
They grow to around 4 inches, so they may need a larger tank than some other species on this list. The peacock gudgeon can be found on sale at most pet stores and online retailers.
They eat small worms, shrimp, crustaceans, and algae. Peacock Gudgeons prefer water temperatures between 76-80 degrees Fahrenheit with a pH level ranging from 6-7.
Bee shrimp (Caridina cantonensis)
Bee shrimp are one of the most popular freshwater invertebrates. They are small and can fit in the palm of your hand. Bee shrimp prefer to live in a planted aquarium with lots of hiding places.
They eat leftover fish food, algae, and other particles on the surface of the water. Bee shrimp will help clean up your tank! Another benefit is that they reproduce quickly and make great feeders for larger fish.
Cherry shrimp (Neocaridina Davidi)
Cherry shrimp are one of the most popular and easiest to care for freshwater shrimp species in the hobby. They are a great addition to any community aquarium because they feed on algae and uneaten food, as well as scavenge dead plant matter.
The only downside is that their population can be out of control if not monitored properly. But if you do keep them at bay, they will work wonders with your tank’s cleanliness and water quality.
In fact, this hardworking little shrimp does so much work that it should actually be considered one of the best rainbow fish tankmates! Additionally, cherry shrimps are safe for both saltwater and freshwater tanks.
Ramshorn Snail (Planorbarius corneus)
The Ramshorn Snail is an excellent choice for anyone who wants a low-maintenance pet snail.
They are easy to care for and come in a variety of colors. These snails are hermaphrodites, meaning they have both male and female genitalia. This means that you can keep two or more together with minimal risk of any unwanted fertilization.
However, if you want to be extra cautious, keep only one snail per tank. Like many other freshwater snails, the Ramshorn has a voracious appetite and will clean your aquarium by eating algae.
Despite its name, this species of snail does not pose any real threat to fish as it lacks the razor-sharp radula needed to break through the fish’s scales.