Madagascar Rainbowfish

Melanotaeniidae sp.

Madagascar Rainbowfish (Melanotaeniidae sp.) — Intermediate care, Peaceful, under Rainbowfish. Minimum tank in the app: 45 US gal min; aim for 73–90°F and pH 6.5–8. Madagascar Rainbowfish are a vibrant addition for those seeking dynamic mid-to-top level swimmers in a community tank.

Madagascar Rainbowfish (Melanotaeniidae sp.) in a planted freshwater aquarium
Care levelIntermediate
TemperamentPeaceful
Min tank size45 US gal min
pH range6.5–8
Temperature73–90°F
Max size3.3 in (8.5 cm)
Captive lifespan6–10 years
SchoolingYes · 6+ recommended

Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.

Natural distribution

Australia / New Guinea

  • Australia & Oceania

Regional colours match the stocking calculator’s origin map.

Madagascar Rainbowfish Tank Setup

Aim for a spacious layout with ample open swimming zones complemented by vegetation to provide both cover and visual barriers. A gentle water flow mimics their natural habitat, while a substrate of sand or fine gravel allows for comfortable navigation. Moderate lighting enhances their colors and encourages natural foraging behavior.

What Do Madagascar Rainbowfishs Eat?

As omnivores, Madagascar Rainbowfish eagerly accept a variety of foods, but be prepared for faster feeding dynamics, especially in mixed tanks. Ensure sufficient food variety to promote health and enhance coloration; consider high-quality flakes or pellets supplemented with live or frozen options to maintain vibrancy and vitality.

Madagascar Rainbowfish Tank Mates

Ideal companions include other peaceful, mid-to-top dwelling species that share similar size and temperament, such as smaller tetras or danios. Avoid overly aggressive or much larger species that could intimidate or outcompete them. Ensure intraspecies harmony by maintaining groups of at least six to distribute any social pressure evenly.

Are Madagascar Rainbowfishs Good for Beginners?

We rate this as intermediate. Budget time for testing, maintenance, and watching behaviour if the water looks fine but the fish do not. Aquarists often underestimate the importance of group size, leading to stress and diminished coloration in isolated individuals. neglecting to provide a balanced diet can result in health issues and poor coloration, while overcrowded tanks can exacerbate aggression and stress levels among all fish.

Building a community? Run the full list through the stocking calculator before you add anything else.

Log tests and reminders in App-aquatic—free, same data you see here.