Top 10 Amazing Rainbowfish for your Next Freshwater Aquarium

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 …


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 schooling fish hang out in the top of the tank so keep the aquarium lid tight to stop them 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-spreading fish that can spawn when they get enough food and water. For a week, add a few spawning mops to your aquarium. Then either take out the eggs or place the whole mop in a separate container. This will prevent adults from predating upon their offspring. Smaller blue-eyes are more likely to die quickly so it is important to breed in order for your colony to continue growing. 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 inches or 6cm)

1. Forktail Rainbowfish

Pseudomugil furcatus

The forktail blue-eye or furcata rainbowfish is a 2-inch (5 cm) beauty known for its brilliant blue eye, yellow-tipped fins that look like little pom-poms, and distinct forked pattern on the tail. As a native of Papua New Guinean rainforests, they enjoy temperatures between 75-80degF (24-27degC), slightly alkaline pH above 7.0, and at least 5deg (90 ppm) GH. Because of their active lifestyle, we like to keep them in a 20-gallon tank or bigger with other peaceful community fish like cory catfish, tetras, and rasboras. For more information, please refer to the complete care guide.

2. Red Neon Rainbowfish

Pseudomugil luminatus

As one of the newest nano rainbowfish introduced to the aquarium trade, the red neon blue-eye is a highly sought-after commodity. Males have a bright red-orange body with an iridescent blue line running along the back and spotting at the fins. At only 1.5 inches (3.8 cm) in length, you could keep a school of 8-10 red neons in a 10-gallon planted aquarium. 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). As a short-lives species, breeding is highly encouraged and can begin as early as 6 months of age.

3. Threadfin and 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. A mix of males and females will help the fish display their best colors. 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-Eyed 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 are capable of living in many conditions, including pH ranging from 5-8 to 70 to 82degF (21-28degC) and soft to very 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 speedy swimmers, measuring in at 2-2.5 inches (5-6cm), would benefit from a 20-gallon or larger tank that allows them to swim freely. These fish are from Sulawesi (Indonesia), and they live in harder water with an alkaline pH higher than 7.0, tropical temperatures of 72-82degF (22-28degC). Although they don’t have a preference for food, like many nano rainbowfishes, they do enjoy tiny foods.

Medium-Sized Rainbowfish (More Than 2 inches, or 6 cm)

6. Boesemani Rainbowfish

Melanotaenia boesemani

Boeseman’s rainbowfish is probably the most well-known rainbowfish from the Melanotaeniidae Family. They have a more almond-shaped body than their smaller cousins, who are torpedo-shaped. The males can reach 4 inches (10 cm) in length and have a bicolored, shiny blue body and an orange back half. These lively fish require a fish tank at least 4 feet in length (1.2m) with a heater set at 75-82degF (24 to 28degC). Discovered in the mountains of West Papua, Indonesia, they can easily handle pH of 6-8 and hard water with 8-20deg (140-360 ppm) GH. To learn more about this beautiful species, read our complete care article.

7. Dwarf Neon Rainbowfish

Melanotaenia praecox

The praecox Rainbowfish is a smaller version of the Melanotaeniidae family’s larger rainbows. At just 3 inches (8cm), it makes a great choice for stocking a small, medium-sized aquarium with a 29-gallon capacity. Males have large, iridescent, blue scales and bright red-orange fins. Females have a silvery, yellow body with fins. While they can handle a broad spectrum of pH and GH, their home in the New Guinea rainforests has harder, alkaline water ranging from 74-80degF (23-27degC). If you have soft water, consider dosing their tank with mineral supplements like Wonder Shell and Seachem Equilibrium to increase the GH. See the complete article about dwarf neons.

8. Turquoise Rainbowfish

Melanotaenia lacustris

The Lake Kutubu rainbowfish, also known as the blue rainbowfish, displays two colors. It has a black horizontal line that divides them into vivid, turquoise and silvery-yellow colors. Similar to the Boesemani Rainbow, they can grow up to 4 inches (10 cm) and will thrive in an aquarium of at least 4 feet (1.2 m). They are found in Lake Kutubu in Papua New Guinea. The water has an alkaline pH higher than 7.0 and is more hardy. Plus, they can handle tropical temperatures from 70-78degF (21-26degC) and get along with other fast-swimming, community species.

9. Red Rainbowfish

Glossolepis incisus

The New Guinea Rainbowfish comes from the alkaline, hard waters in Western New Guinea, Indonesia. It’s known for its brightly colored body and scattered of shiny scales at the lateral. They are one of the largest rainbowfish in the hobby and can grow to almost 12 inches (12 cm) in length. To be able to care for a school of six or more, you will need a minimum of a 4 foot aquarium. Like most of the other rainbows in the second half of our list, their appetites are hearty but their mouths are relatively small, so feed them a variety of appropriate-sized, meaty foods – such as krill flakes, Vibra Bites, bloodworms, daphnia, and brine shrimp.

10. Lake Tebera Rainbowfish

Melanotaenia herbertaxelrodi

Lake Tebera lies in the midst of mountainous jungles in Papua New Guinea. It is surrounded by tropical waters that are alkaline and high in minerals. 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. At 3.5 inches (9 cm) in length, it can live in a 40-gallon breeder aquarium with other energetic tank mates of a similar size. These include rainbowfish, loaches (barbs), gouramis and giant danios as well as peaceful catfish.

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.