Neon Tetra

Paracheirodon innesi

Also known as: Neon

Water Parameters

• Temperature: 21–25°C
• pH: 4–7.5
• Hardness (GH): 18–215 ppm (1–12 dGH)

Values above are general hardness (GH). For carbonate hardness (KH), the buffer that keeps pH stable, see the water parameters guide.

Care Summary

One of the most popular community fish ever kept, prized for its iridescent blue and red stripe. Deceptively delicate despite its beginner reputation: modern farm-bred neons are less hardy than their wild ancestors and prone to neon tetra disease, an incurable parasitic illness. Best added to a mature, fully cycled tank, never a new one. Schools tightly in the middle of the water column. They do best in soft water with a low carbonate hardness (KH); hard, high-KH water keeps the pH too high for good colour and rules out breeding.

Tankmates

A peaceful schooling species that must be kept in groups of at least 6, ideally 10 or more for a healthy school. Their small size and bright colouration makes them targets for larger or aggressive fish, including adult angelfish (which historically prey on them in the wild) and bettas (which may mistake the flash of colour for a rival). Best in soft, slightly acidic water; struggles in hard, alkaline water typical of many Australian municipal supplies.

Compatible with

• Cardinal Tetra
• Bronze Corydoras
• Harlequin Rasbora
• Ember Tetra
• Cherry Shrimp
• Otocinclus
• Pencilfish
• Marble Hatchetfish
• Black Neon Tetra
• Lemon Tetra
• Diamond Tetra
• Black Phantom Tetra
• Flame Tetra

Avoid keeping with

• Betta
• Angelfish
• Large Cichlids
• Fin Nippers
• Electric Yellow Cichlid
• Bumblebee Goby

Common Problems

• neon tetra disease (incurable)
• ich
• stress from being kept in groups smaller than 6
• sensitivity to water parameter swings

Sources: seriouslyfish.com, fishbase.org · Last updated: 2026-06-18