AQUATIC PLANTS & LIVESTOCK

Neon Tetra

Small shoaling characin; needs soft acidic water, a group of ten or more and a mature tank.

Stocking stage Plants

Unplug before servicingHands out of the water firstDrip loop on every cableTest before you dose30 ppm CO₂ ceilingCycle before stocking

Plants

Specification
Adult size	3–4 cm
Group size	10+ minimum
Water	Soft, acidic
Temperature	22–26 °C
Temperament	Peaceful shoaler
Tank minimum	60 cm for a group

Technical parameters
pH range	6.0–7.0
GH	2–8 dGH
KH	0–4 dKH
Minimum tank age	4–6 months
Swim level	Mid-water
Lifespan	5–8 years

The neon tetra is the fish most people picture when they picture a planted tank: a 3 cm characin with an iridescent blue stripe and a red rear band, swimming in a tight shoal. It is also one of the most commonly mistreated, because it is cheap, it is sold to beginners, and its requirements are specific.

Neons are a blackwater species. They come from soft, acidic, tannin-stained water and they do badly in hard, alkaline conditions — not immediately, but over months, with faded colour and a susceptibility to neon tetra disease and ich. They also need a group. Six is the minimum for them to feel safe, ten or more is where the shoaling behaviour that makes them worth keeping actually appears.

The third requirement is a mature tank. A neon dropped into a tank that has been running for two weeks is being asked to survive the tail end of a nitrogen cycle it did not evolve for. Four to six months of stability is the realistic threshold.

Safety and welfare

Acclimatise slowly. Drip-acclimatise over 45–60 minutes, particularly for the pH difference between shop water and tank water.
Never add neon tetras to a tank that has not completed its cycle. Ammonia burns their gills before it is measurable as a visible problem.
Quarantine new fish for three weeks. Neon tetra disease is incurable and spreads through a shoal.

Using it well

A dark background and dim lighting bring out the blue stripe. In a brightly lit white tank they look washed out.

Keep them in a group of ten or more. A shoal of three hides constantly and looks like a tank with no fish in it.

Feed small foods — micro granules, daphnia, baby brine shrimp. Their mouths are tiny and large flakes are ignored.

Compatible with

Cherry shrimpNerite snailAnubiasJava fernMonte Carlo

Worth knowingWill eat shrimp fry. Adult cherry shrimp are safe; shrimplets are not.

Note. Parameters are conventional ranges across the category, not the claim of any one manufacturer. Nothing on this page is for sale and no outcome for any plant or animal is guaranteed. Simulator output elsewhere on this site is a simplified model, not a measurement — confirm everything with a test kit and the equipment's own instructions.

Neon Tetra

Using it well

Compatible with

Works alongside