Neon Tetra

Scientific name: Paracheirodon innesi

Adult size: about 3 cm

Origin: western Amazon basin, Colombia, Peru and Brazil

Water: 21–25 °C, pH 4.0–7.5, soft to moderately hard (1–12 dGH)

Group: 8–10 or more

Diet: omnivore, small dried, frozen and live foods

Temperament: peaceful, schooling

The neon tetra is one of the most recognised small fish in the hobby: an electric blue stripe from nose to adipose fin, with a red band on the rear half of the body and a silver-white belly. Adults reach about 3 cm. It comes from slow, shaded, tannin-stained streams in the western Amazon, where the water is soft and acidic, and it looks its best in a tank that echoes that, with dark substrate, plants and a little leaf litter. Tannins are the tea-coloured compounds that leach from wood and leaves. It is a schooling fish, meaning it stays close to others of its kind for safety; kept in ones and twos it hides and fades, so a group of eight to ten is the sensible starting point. It is peaceful and pays little attention to other fish of a similar size. Neons are omnivores that eat small invertebrates, algae and fallen fruit in the wild.

Water: 21–25 °C and pH 4.0–7.5, with hardness 1–12 dGH. GH is a measure of dissolved calcium and magnesium; lower numbers mean softer water. Keep conditions stable rather than chasing exact figures.

Tank and planting: a planted tank with open swimming room in the middle, subdued light and dark substrate. Add the fish only once the tank is cycled, meaning the filter bacteria that convert fish waste are established.

Feeding: a good quality small flake or granule as the staple, plus regular meals of frozen or live daphnia, brine shrimp and bloodworm. Feed small amounts once or twice daily.