Top 10 Amazing Rainbowfish for Your Next Freshwater Aquarium

Rainbowfish and blue-eyes are a unique group of colorful, community fish that can be found primarily in the freshwater habitats of Papua New Guinea, Indonesia, and Australia. These energetic schooling fish usually hang out in the top half of the fish tank, so make sure to keep a tight aquarium lid to prevent them from jumping out. We recommend that you keep more females than males because they are more vibrant than their male counterparts.

You can also have fun with both sexes breeding them at home. Rainbowfish are egg scatterers. They will spawn as long as you provide them with good food and clean water. You can add a few eggs to your aquarium and leave them there for about a week. After that, you can either remove the eggs from the tank or put the entire mop in a separate container. This will keep the adults away from their offspring. The small blue-eyes can be very fragile so you will need to breed them. Although larger rainbowfish take longer to mature, their stunning appearance is well worth the effort. To help you decide which species to start with, let’s talk about 10 different species that are popular in the aquarium hobby and which one is right for you.

Nano Rainbowfish (Smaller Than 2.25 inches or 6 cm).

1. Forktail Rainbowfish

Pseudomugil furcatus

The forktail rainbowfish, also called furcata or furcata blue-eye, is a 2-inch (5cm) beauty. It is distinguished by its distinctive forked tail and yellow-tipped fins. They live in Papua New Guinean rainforests where they can enjoy temperatures as high as 75-80F (24-27degC), slightly acidic pH above 7.0 and a minimum of 5deg (990 ppm) GH. We keep them in a 20 gallon tank with other peaceful fish such as cory catfish, Tetras and Rasboras due to their active lifestyle. For more information, please refer to the complete care guide.

2. Red Neon Rainbowfish

Pseudomugil luminatus

The red neon blue-eye, one of the most sought-after fish in the aquarium trade is the latest nano rainbowfish. The males have a bright red-orange body with an iridescent blue line running along the back and spotting at the fins. You could house 8-10 red neons in a 10 gallon planted aquarium, each measuring 1.5 inches (3.8cm). The fiery colors of these neons are stunning when they swim in front of a lush green forest of aquarium plants. They were originally collected from Papua, Indonesia and can be kept in pH of 6.0-7.5 and temperatures between 68-78degF (20-26deg C). They are a short-lived species so breeding is strongly encouraged.

3. Threadfin or Featherfin Rainbowfish

Iriatherina werneri

The threadfin rainbowfish, which measures in at 2 inches (5 cm), is one of the more robust specimens among the nano rainbowfish. Their common name comes the male’s long, wispy fins and lovely lyretail. Their coloration may vary depending on where they were found. They can be yellow, black or blue depending on where they were found. Getting a mix of both males and females will encourage the fish to show their most vibrant hues. Featherfin rainbows are found in slow-moving waterways of New Guinea or Australia that are choked from plant life. Therefore, they will appreciate gentle filters, pH between 6.0 and 7.5, tropical temperatures of 74 to 80degF (23 to 27 degC).

4. Gertrude’s Spotted-Blue-Eye Rainbowfish

Pseudomugil gertrudae

This 1.25-inch (3 cm) rainbowfish has a striking appearance because of its yellowy body, bright blue eyes, and pale fins speckled with dark spots. Their natural habitats consist of swampy, vegetation-filled waters of Australia, New Guinea, Indonesia and the Aru Islands. These waters often contain lots of driftwood, fallen leaves, and other debris. They can live in any pH level between 5-8 and 70-82degF (22 to 28 degC), as well as soft to hard water. They breed readily to compensate for their short lifespan, so add lots of yarn mops and floating plants to encourage spawning behavior.

5. Celebes Rainbowfish

Marosatherina ladigesi

Similar to the furcata Rainbowfish, the celebes Rainbow has a yellow tail with a fork and yellow and dark fins. The back half of the body is covered in a neon-blue horizontal stripe. These fast swimmers are 2 to 2.5 inches (5 to 6 cm) in length and would love a 20-gallon tank or larger. This will allow them enough space to move around freely. As residents of Sulawesi, Indonesia, they come from harder waters with alkaline pH above 7.0 and tropical temperatures between 72-82degF (22-28degC). Like many nano rainbowfish they are not fussy but will eat small food that is easy to digest.

Medium-Sized Rainbowfish (More than 2.5 inches or 6cm)

6. Boesemani Rainbowfish

Melanotaenia boesemani

Boeseman’s rainbowfish are probably the most famous rainbowfish that come from the Melanotaeniidae family, which traditionally have more almond-shaped profiles compared to the torpedo-shaped bodies of their smaller cousins. Males can reach 4 inches (10 cm) and have an unusual bicolored body, with a shiny orange front and back and a blue front. These vibrant fish require a fish aquarium at least 4ft in length and a heater set for 75-82degF (24-28%C). They were found in West Papua (Indonesia) and can handle pH 6-8 and hard water 8-20deg (140-356 ppm). This article will provide more information about this amazing species.

7. Dwarf neon rainbowfish

Melanotaenia praecox

The praecox praecox is a small, 3 inch (8 cm) long rainbowfish in the Melanotaeniidae group. It’s a good option to stock a medium-sized, 29,-gallon aquarium. Males have large, iridescent, blue scales and bright red-orange fins. Females have a silvery, yellow body with fins. Their home in New Guinea rainforests, however, has alkaline water that ranges from 74 to 80degF (23 – 27degC). To increase their GH, you can douse their tank with mineral supplements such as Wonder Shell or Seachem Equilibrium. You can read the entire article about dwarf neons.

8. Turquoise Rainbowfish

Melanotaenia lacustris

The Lake Kutubu Rainbowfish or Blue Rainbowfish has two colors. They are separated by a black horizontal dividing line. Similar to the Boesemani Rainbow, they can grow up to 4 inches (10 cm) in length and would thrive in a 4-foot (1.25 m) aquarium. Their common name may be a hint that they are found in Lake Kutubu (Papua New Guinea), which has an alkaline pH over 7.0 and hard water. They are able to withstand tropical temperatures of 70-78degF (21-26degC), and can co-exist with other community-based, fast-swimming species.

9. Red Rainbowfish

Glossolepis incisus

The New Guinea Rainbowfish comes from the alkaline, hard water of Western New Guinea in Indonesia. It is well-known for its brightly colored body and scattered of shiny scales at the lateral. As one of the larger rainbowfish in the fishkeeping hobby, they can reach almost 5 inches (12 cm) in size and also require a 4-foot aquarium at minimum to handle a school of 6 or more. The second half of our rainbowfish list is similar in that they have large appetites but small mouths. So feed them appropriate-sized, meaty food such as Vibra Bits, Krill Flake, Vibra Bites bloodworms, brine shrimp, and daphnia.

10. Lake Tebera Rainbowfish

Melanotaenia herbertaxelrodi

Lake Tebera is surrounded by mountainous jungles in Papua New Guinea, where the waters are alkaline, high in minerals, tropical in temperature (68-79degF or 20-26degC), and full of aquatic plants. M. herbertaxelrodi can be difficult to find in pet shops, but its golden yellow body, black horizontal stripes, and red-orange-colored fins make it worth the effort. It is able to live with other active tank mates up to its size of 3.5 inches (9 cm). Other rainbowfish, loaches and gouramis are also available.

Given their love for protein, avoid putting them with dwarf shrimp, baby fish, and anything small enough to fit in their mouths.

While Aquarium Co-Op does not ship live fish, you can check out the amazing selection of rainbowfish offered by our preferred online retailers. Enjoy setting up a fun, action-packed aquarium filled with your favorite species of rainbowfish.