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. To ensure the brightest colors, keep more males than females.
Having both sexes also means that you can have fun breeding them at home. Rainbowfish are egg-spreading fish that can spawn when they get enough food and water. To prevent predators from preying on your offspring, simply add a few spawning mops to the aquarium. The smaller blue-eyes tend to be fairly short-lived, so breeding will help keep your colony going. The stunning appearance of larger rainbowfish makes it worth the effort. However, they can take longer to mature. Let’s discuss 10 species that are very popular in aquarium hobby. Which one is best for you?
Nano Rainbowfish (Smaller Than 2.5 inches or 6 cm)
1. Forktail Rainbowfish
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. The forktail blue-eye is a native of Papua New Guinea’s rainforests. They can be found in temperatures between 75-80F (24-27degC), slightly acidic pH above 7.0 and at least 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. Read the full care guide for more details.
2. Red Neon Rainbowfish
Red neon blue-eye is one of the newest aquarium fish introduced to the market. Males have a vibrant red-orange body, iridescent blue eye and line running along its back, and spotting on 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
One of the deeper-bodied specimens amongst the nano rainbowfish is the 2-inch (5 cm) threadfin rainbowfish. Their common name derives from the male’s long, wispy tail and beautiful lyretail. Depending on the locale they were found, their coloration can include yellow, black, blue, and even reddish-pink. A mix of males and females will help the fish display their best colors. Featherfin rainbows inhabit slow-moving waterways in New Guinea and Australia that are choked with plant life, so they will appreciate a gentle filter, pH between 6.0-7.5, and tropical temperatures of 74-80degF (23-27degC).
4. Gertrude’s Spotted blue-Eyed Rainbowfish
The 1.25-inch (3-cm) rainbowfish is striking due to its bright yellow body and bright blue eyes. Its pale fins are speckled with dark spots. Their natural habitats include swampy, vegetation-filled water in Australia, New Guinea, Indonesia, and the Aru islands of Indonesia. There are often lots of driftwood and fallen leaves. They are surprisingly hardy enough to live in a wide range of parameters, including pH from 5-8, 70-82degF (21-28degC), and 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
The celebes rainbow is similar to the furcata rainbowfish. It has a yellow fork at its tail and yellow and black fins with fringes and a horizontal stripe running down its back half. 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. They are native to Sulawesi in Indonesia and come from hard water with an alkaline pH of 7.0 and tropical temperatures between 72-82degF (22-24degC). Although they don’t have a preference for food, like many nano rainbowfishes, they do enjoy tiny foods.
Medium-Sized Rainbowfish (More than 2.5 inches or 6cm)
6. Boesemani Rainbowfish
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 grow up to 4 inches (10cm) in length, and they have a unique bicolored body that has a shiny blue front half and an orange back. Therefore, these lively fish need a fish tank of at least 4 feet (1.2 m) in length with a heater set to 75-82degF (24-28degC). 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
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. Although they are able to handle a broad range of pH and GHG, their habitat in New Guinea rainforests is more alkaline, ranging between 74-80degF (23-25degC). You can increase their GH by adding mineral supplements to your tank like Wonder Shell and Seachem Equilibrium if you have soft water. See the complete article about dwarf neons.
8. Turquoise Rainbowfish
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). As you may have guessed by their common name, they are found in Lake Kutubu of Papua New Guinea, which has alkaline pH above 7.0 and harder water. They are able to withstand tropical temperatures of 70-78degF (21-26degC), and can co-exist with other community-swimming species.
9. Red Rainbowfish
The New Guinea rainbowfish is a native of the hard water of Western New Guinea, Indonesia. It is known for its bright red body, and the scattered shiny scales along its lateral line. 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. 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
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 can grow to 3.5 inches (9cm) in length and live in a 40 gallon aquarium with other tank mates of 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.