Red Rainbowfish
Melanotaenia duboulayi
Description
The Red Rainbowfish is a colorful and active species, known for its vibrant red and orange hues, which make it a popular choice in aquariums. Adult males are especially bright, with deep red and orange colors that shine under aquarium lighting. Females, while still colorful, tend to have a more subdued coloration. The body of the Red Rainbowfish is elongated and streamlined, ideal for swimming in schools. These fish are peaceful and social, preferring to be in groups of at least six or more individuals. They are known for their energetic swimming behavior and enjoy the open water in the middle to upper parts of the tank. The vibrant coloration and lively nature of the Red Rainbowfish make it an excellent addition to community tanks.
Habitat Origin
Native to the freshwater lakes and rivers of Papua New Guinea, specifically found in the Lake Habbema region and other areas in New Guinea. These fish typically inhabit clear, slightly acidic waters with moderate flow and plenty of aquatic plants. They are found in both still and slow-moving waters and thrive in warm, well-oxygenated environments with stable water conditions.
Aquarium
Ideal Number in Aquarium: At least 6 individuals, as they are schooling fish and feel more secure in groups.
Favorite Food
Red Rainbowfish are omnivores and will eat a variety of foods. They can be fed high-quality flake food, pellets, live or frozen foods such as brine shrimp, bloodworms, and daphnia. They also graze on small plant matter and algae, so they benefit from a varied diet that includes both animal and plant-based foods. A well-balanced diet is important to help maintain their vibrant coloration and overall health.
Behavior:
Red Rainbowfish are peaceful, active, and social fish that do well in schools. They are generally calm, but their energetic swimming habits make them an exciting addition to a community tank. These fish swim in the middle and upper parts of the aquarium, where they are often seen moving in coordinated groups. They are not aggressive and are compatible with other small, peaceful fish. As schooling fish, they feel more secure when kept in groups, and their bright colors and energetic behavior add life to the tank. They may become shy if kept alone, so it is important to house them in groups.
Special Care:
Red Rainbowfish are relatively hardy but require stable water conditions to thrive. They need a well-maintained aquarium with regular water changes and good filtration. Providing plenty of swimming space and some plants or decorations for hiding spots is important to make them feel secure. A planted tank works well, as they enjoy swimming through plants and appreciate a more natural environment. Additionally, since they are active swimmers, it’s important to ensure that the tank is spacious enough to allow them to swim freely.
Compatibility with Other Fish:
Yes, Red Rainbowfish are compatible with many peaceful species. They can be housed with other tetras, rasboras, peaceful cichlids, and small catfish. It’s best to avoid housing them with large or aggressive fish that may stress or harm them. As they are schooling fish, they do well when housed with other schooling species. Red Rainbowfish are ideal for a community aquarium with peaceful species and ample swimming space.
Breeding Setup
Setting up a separate breeding tank is strongly recommended for Red Rainbowfish to ensure the eggs and fry are safe from predation and that water parameters remain stable. A 100-liter (26-gallon) tank is ideal for a breeding pair. Maintain pH between 6.5 and 7.5, temperature at 26–28°C, and GH 4–12 dGH. Use a gentle sponge or internal filter to avoid strong currents. Provide fine substrate such as sand or gravel, and include live plants like Java moss, Hornwort, or Anubias for egg-laying surfaces. Floating plants and moderate lighting help mimic their natural habitat.
Conditioning for Breeding
Condition Red Rainbowfish with a protein-rich, varied diet to prepare them for spawning. Offer high-quality flakes, live foods like brine shrimp, daphnia, and bloodworms, as well as frozen foods. Good nutrition enhances fertility and strengthens both sexes. Perform 25% weekly water changes to maintain water quality and encourage breeding behavior through fresh, stable conditions.
Spawning Process
Red Rainbowfish are egg scatterers. Males court females by displaying vivid colors and active swimming behavior. When the female is ready, she lays 50–100 adhesive eggs on plants, rocks, or glass. The male fertilizes the eggs immediately after. Because adults do not guard their eggs, it is crucial to remove them post-spawning to prevent egg predation.
Fry Care
Eggs hatch within 24–48 hours, depending on temperature. Newly hatched fry rely on their yolk sacs before becoming free-swimming. Once mobile, feed them infusoria, liquid fry food, or microscopic algae. After a few days, introduce baby brine shrimp or finely ground flakes. Maintain excellent water quality with daily 10–15% water changes, and keep the temperature stable at 26–28°C. Regularly test ammonia, nitrite, and nitrate levels to ensure a safe environment for fry.
Important Notes
Red Rainbowfish reach sexual maturity at 6–12 months. Males are more colorful—showing deep red, blue, and yellow hues—while females appear larger and less vibrant. During breeding, males display heightened coloration to attract females. To reduce stress, avoid aggressive tankmates, ensure ample hiding spots, and maintain stable, peaceful conditions. A stress-free environment increases the chances of a successful spawn and healthy fry development.