Neon tetra

Paracheirodon innesi

Freshwater Tetras & schoolers Beginner
Size
3–4 cm
Tank
75 L min
Temp
22–26 °C
pH
6.0–7.0
School
8+
Lifespan
5–8 yrs

Identification

Slender 3–4 cm body with an iridescent blue lateral stripe from eye to adipose fin and a red band along the rear half of the body. Often confused with the cardinal tetra, whose red runs the full length.

Tank size

75 litres (20 US gallons) for a school of 8–12. Longer footprints beat tall ones; neons swim mid-water in a horizontal band.

Temperament

Peaceful and shy. Schools loosely when relaxed, tightly when stressed. Ignores other species entirely.

Diet

Omnivore. Crushed flake or micro-pellet daily, frozen daphnia or baby brine shrimp twice a week. Feed small; they have tiny mouths and slow stomachs.

Breeding

Egg-scatterer. Needs very soft water (GH under 3), near-darkness, and a separate spawning tank. Rarely achieved at home; almost all stock is farm-bred.

Compatibility

Safe with any peaceful fish under 8 cm. Avoid angelfish, which eat them, and bettas in small tanks.

Common diseases

Neon tetra disease (Pleistophora) is incurable and shows as fading colour and a lumpy spine; remove affected fish. Ich responds to heat and salt.

Lifespan

5–8 years in stable water. Most die early from being added to tanks that have not finished cycling.

Difficulty

Beginner, with one caveat: add them to an established tank, never a new one.

Water parameters

Temperature 22–26 °C Cooler end extends lifespan
pH 6.0–7.0 Tolerates to 7.5 once acclimated
Hardness 1–10 dGH Soft preferred
Ammonia / nitrite 0 ppm Very sensitive
Nitrate < 20 ppm Weekly 25% change