
Turquoise Rainbowfish
Melanotaenia lacustris
Family: Melanotaeniidae • Origin: Various
Turquoise Rainbowfish (Melanotaenia lacustris) is a peaceful rainbow reaching 5 inches. Keep in groups of 6+. Minimum tank: 20 gallons.
Is Turquoise Rainbowfish Right for Your Tank?
Turquoise Rainbowfish is an excellent choice for beginners — rated "intermediate" difficulty (2/5). They're hardy, forgiving of minor water parameter fluctuations, and generally easy to feed. A 20-gallon tank minimum is standard — most community setups will accommodate them.
With a peaceful temperament, Turquoise Rainbowfish makes a great community fish. They coexist well with other non-aggressive species of similar size. This is a schooling species — keep at least 6 together, or they may become stressed and display abnormal behavior. Expected lifespan: 8 years with proper care.
Common Mistakes with Turquoise Rainbowfish
Keeping fewer than 6 together
Turquoise Rainbowfish is a schooling species — they need a group of at least 6 to feel secure. Lone or paired individuals become stressed, hide constantly, and may develop health issues or aggression.
Putting them in a tank under 20 gallons
Many beginners underestimate tank size needs. Turquoise Rainbowfish requires at least 20 gallons — ideally 30. Cramped tanks lead to stunted growth, aggression, and poor water quality.
Care Tips
- • Max size: 5"
- • Temp: 72-79°F
- • pH: 7-8
- • Schooling: keep 6+
- • peaceful temperament
Feeding: Standard omnivore diet appropriate for Melanotaeniidae.
Compatibility Notes: Typical peaceful Melanotaeniidae species.
Tank Setup & Water Parameters
Tank Requirements
- Minimum Tank Size
- 20 gallons
- Recommended Tank Size
- 30 gallons
- Swimming Level
- middle
- Minimum School Size
- 6+ fish
Water Parameters
- Temperature
- 72–79°F
- pH Range
- 7–8
- Hardness (dGH)
- 5–15
- Water Type
- freshwater
Behavior & Temperament
- Temperament
- peaceful
- Aggression Level
- 1/5
- Schooling
- Yes
- Territorial
- No
- Fin Nipper
- No
- Predatory
- No
- Diet Type
- omnivore
- Growth Rate
- moderate
Typical peaceful Melanotaeniidae species.
Breeding
- Breeding Type
- egg layer
- Breeding Difficulty
- moderate
- Lifespan
- 8 years
Ideal For
Compatible Tank Mates
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Guppy
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