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. While males are more vibrant than females, we recommend keeping more females than males to ensure that the boys show off their brightest colors.
Having both sexes also means that you can have fun breeding them at home. Rainbowfish are egg scatterers that will regularly spawn if you give them plenty of good food and clean 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. Blue-eyes smaller than 10 cm are usually very short-lived so breeding is a good idea to keep them happy. The stunning appearance of larger rainbowfish makes it worth the effort. However, they can take longer to mature. 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 2.5 Inches or 6 Cm)
1. Forktail Rainbowfish
Furcata rainbowfish, also known as the forktail blueeye, is a 2-inch (5.5 cm) beauty. It’s well-known for its bright blue eyes, yellow-tipped fins and distinctive forked 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. Their active lifestyle means that they are kept in 20-gallon tanks or larger with other peaceful community fish, such as cory catfish and tetras. For more information, please refer to the complete care guide.
2. Red Neon Rainbowfish
Red neon blue-eye is one of the newest aquarium fish introduced to the market. The males are bright red-orange with a line running down its back and spotting on their fins. With a length of 1.5 inches (3.8 cm), you can keep 8-10 red neons in your 10-gallon tank. The fiery colors of these neons are stunning when they swim in front of a lush green forest of aquarium plants. They can be kept at a pH of 6.0 to 7.4 and temperatures between 68 and 78 degrees F (20 and 26 degrees C) since they were originally taken from Papua in Indonesia. Breeding is encouraged as a species with a short life span. It can be started as early as 6 months old.
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-Eye 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 capable of living in many conditions, including pH ranging from 5-8 to 70 to 82degF (21-28degC) and soft to very hard water. In order to compensate for their short lives, they breed quickly. To encourage this behavior, add lots of yarn mops and floating plants.
5. Celebes Rainbowfish
Similar to the furcata rainbowfish, the celebes rainbow has a yellow fork in its tail, as well as yellow and black fins with a fringe and a neon blue, horizontal stripe down the back half of its body. 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). They aren’t picky eaters like most nano rainbowfish but prefer small foods such as nano pellets and crushed flakes.
Medium-Sized Rainbowfish (More Than 2.5 inches or 6 cm)
6. Boesemani Rainbowfish
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. 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. 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). They were found in West Papua (Indonesia) and can handle pH 6-8 and hard water 8-20deg (140-356 ppm). Read our full care article to learn more about this wonderful species.
7. Dwarf Neon Rainbowfish
The praecox rainbowfish measures 3 inches (8cm) in length. It is one of the smaller rainbows within the Melanotaeniidae Family. This makes it a good choice for stocking a medium-sized aquarium, 29-gallon in size. 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). To increase their GH, you can douse their tank with mineral supplements such as Wonder Shell or Seachem Equilibrium. 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. They grow to 4 inches (10 cm) long and can be kept in an aquarium that is at least 4 ft (1.2 m) high. 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
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. The New Guinea rainbowfish is one of the larger fish in the fishkeeping hobby. They can reach nearly 5 inches (12cm) in size. A 4-foot aquarium is required to house a school for 6 or more. They are similar to the rest of the rainbowfish in our second half, but have a smaller appetite. Therefore, they need a 4-foot aquarium at minimum.
10. Lake Tebera Rainbowfish
Lake Tebera is surrounded in Papua New Guinea’s mountainous jungles. The waters of Lake Tebera are alkaline, rich in minerals, tropical in temperature (68 to 79°F or 20 to 26°C), and full aquatic plants. M. herbertaxelrodi may be harder to find at pet shops but its golden yellow body and black horizontal stripe along with red-orange fins makes 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. 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.