Celebes Rainbowfish

Also known as: Marosatherina ladigesi

The Celebes Rainbowfish is a slender, iridescent fish native to the clear streams of Sulawesi, displaying subtle blue-green hues along its body with a faint lateral stripe. The Celebes Rainbowfish originates from Endemic to Sulawesi (Celebes), Indonesia, specifically found in the Maros region and surrounding freshwater streams and rivers with clear, flowing water and dense vegetation., reaches Adult size: 5-6 cm in captivity, typically lives 3-5 years, and is kept at 24-28°C (75-82°F). Individual fish vary, so treat this as a general guide rather than a guarantee.

Species at a glance

Origin: Endemic to Sulawesi (Celebes), Indonesia, specifically found in the Maros region and surrounding freshwater streams and rivers with clear, flowing water and dense vegetation.
Adult size: Adult size: 5-6 cm (2-2.4 inches)
Life span: 3-5 years
Temperament: Peaceful and active schooling fish; best kept in groups of 6 or more; non-aggressive and compatible with other small, peaceful community fish.
Tank size: Minimum 60 liters (16 gallons) for a small school; 80+ liters (21+ gallons) recommended for larger groups or community setups.
Water temp: 24-28°C (75-82°F)
pH range: 6.0-7.5
Diet: Omnivorous; feeds on small invertebrates, algae, and detritus in the wild; in captivity, accept high-quality flakes, micro pellets, frozen or live foods such as brine shrimp, daphnia, and bloodworms.
Other names: Marosatherina ladigesi

About the Celebes Rainbowfish

The Celebes Rainbowfish is a slender, iridescent fish native to the clear streams of Sulawesi, displaying subtle blue-green hues along its body with a faint lateral stripe. Males are more colorful than females, especially during breeding, showing enhanced finnage and brighter tones. They are active swimmers that prefer the middle and upper water layers, thriving in well-planted tanks with gentle flow. Their peaceful nature and striking appearance make them a popular choice for planted community aquariums.

Lifespan and health

With optimal care, Celebes Rainbowfish typically live 3-5 years in captivity, though some individuals may reach up to 6 years under ideal conditions. Lifespan is strongly influenced by water quality, diet consistency, and stress levels; fish kept in stable, well-maintained tanks with proper schooling behavior and nutrition show significantly better longevity. Regular monitoring of water parameters and prompt correction of deviations are essential to maximizing their lifespan. Common health issues include fungal infections (often appearing as cotton-like growths on fins or body) and bacterial infections like fin rot, usually triggered by poor water quality or physical damage from aggressive tankmates. Parasitic infestations such as Ich (white spot disease) can occur if new fish are not quarantined or if temperatures drop suddenly. Preventive measures include maintaining excellent filtration, avoiding overcrowding, quarantining new arrivals for 2-4 weeks, and providing a varied diet rich in vitamins to support immune function.

Overview

Care and tank setup

Tank setup should include a densely planted aquarium with fine-leaved plants like Java moss, Hornwort, or Vallisneria to provide cover and mimic their natural habitat; use a sandy or fine gravel substrate and add driftwood for natural aesthetics. Maintain gentle water flow with a sponge filter or low-output canister filter to avoid stressing these active swimmers; lighting should be moderate to support plant growth without causing algae overgrowth. Perform weekly 25% water changes to maintain water quality, as they are sensitive to nitrate buildup. Water parameters must be stable: keep temperature between 24-28°C (75-82°F), pH between 6.0-7.5, and hardness soft to moderately soft (5-12 dGH). Avoid sudden fluctuations in temperature or chemistry, as they are prone to stress-related issues. Feed small amounts 2-3 times daily, offering only what they can consume within 2-3 minutes to prevent overfeeding and water contamination. Tankmates should be peaceful, similarly sized species such as other small rainbowfish (e.g., Pseudomugil spp.), tetras, rasboras, Corydoras catfish, and small shrimp like Amano or Cherry shrimp. Avoid aggressive or fin-nipping fish such as tiger barbs or large cichlids; also avoid overly active or boisterous species that may outcompete them for food or cause stress through constant chasing.

Adding a Celebes Rainbowfish? Research the species’ adult size and temperament carefully, quarantine new fish before introducing them to your tank, and buy from reputable aquarium stores or breeders.

Breed information on this page is based on the Wikipedia article on the Celebes Rainbowfish, supplemented with additional research. Reviewed for accuracy.