Neon Tetra

Paracheirodon innesi is native to blackwater and clearwater streams and tributaries of the upper Amazon River basin - primarily Peru, Colombia and Brazil. In the wild it inhabits heavily shaded, slow-moving waters under dense rainforest canopy: soft, slightly acidic, tannin-dark water with minimal direct light. Temperature range typically 20–26°C.

First collected by French aquarium fish exporter Auguste Rabaut in remote Peru in 1934 - the first live specimens in Europe were extraordinary novelties, reportedly exhibited at the Natural History Museum in Paris and attracting large crowds. By the mid-20th century it had become one of the most widely traded freshwater fish in the world. Today virtually all Neon Tetras in the trade are commercially bred, primarily in Southeast Asia.

No licence required in Australia. Never release into Australian waterways.

Minimum 60 litres for a school of ten or more in a community setting; 40 litres for a dedicated species tank of six to eight. A longer footprint is preferred - Neons are active horizontal swimmers.

Setup should replicate the dimly lit, tannin-stained Amazonian tributary: dark substrate (black or dark brown sand), dense planting with mid-water and floating plants, driftwood and Indian almond leaves for tannins and mild acidification. The electric blue and red colouration is most vivid and most visible against dark substrate under moderate, natural-toned lighting.

Temperature 22–26°C; pH 6.0–7.0; hardness 1–10 dGH. The tank must be fully cycled before any fish are introduced - Neons are sensitive to ammonia and nitrite. Weekly 25% water changes. Gentle filtration only (sponge filter or low-flow internal). Strong currents stress this species. Ensure the tank is fully mature before adding Neons.

Neon Tetras are omnivores with very small mouths - all foods must be fine enough to consume. A quality micro-pellet or finely crushed tropical flake should form the dietary staple; supplement two to three times per week with frozen or live micro-foods: baby brine shrimp, daphnia, micro worms and finely chopped bloodworm. These small proteins enhance colour and condition.

Feed small amounts twice daily - only what the school consumes in two to three minutes. Neons are mid-water feeders; surface-floating foods may be ignored. Varied diet is the most reliable way to maintain vivid iridescent colouration.

Fish are not handled. Minimise netting. Use a fine soft mesh net when necessary.

A very small fish that must be kept in a school of at least six - ideally ten or more - to display natural behaviour. Individual fish in small groups become stressed, lose colour and are more vulnerable to disease. They occupy the mid-water column and show no aggression toward any similarly sized or larger peaceful species.

Compatible tank mates must be chosen carefully given the Neon Tetra's very small size - virtually any fish that can fit one in its mouth will eat it. Suitable companions: other small peaceful tetras (Ember, Rummy-nose), Harlequin Rasboras, small Corydoras, small Otocinclus, Dwarf Gouramis, Honey Gouramis, Endler's Livebearers. Avoid: Angelfish (will eat Neons when large enough), large barbs, cichlids of any kind, Bettas and any fish significantly larger than the Neon.

A densely planted tank with varied depths, dark substrate and floating plants allows natural mid-water schooling. A large, active school in a well-planted tank is its own enrichment - the coordinated movement and colour display of a healthy Neon school is one of the most rewarding observations in freshwater fishkeeping.

Varied feeding - rotating micro-pellets, frozen daphnia, baby brine shrimp and micro worms - stimulates natural foraging. Indian almond leaves and driftwood create the tannin-stained environment the species thrives in and visually enhance colouration.

Neon Tetra Disease (NTD): The most serious health concern - caused by the microsporidian parasite Pleistophora hyphessobryconis. Presents as colour fading in patches (blue and red bands become pale or white in affected areas), followed by body wasting, curved spine and death. No effective treatment exists. Prevention only: quarantine all new fish for two to four weeks, maintain excellent water quality, remove affected individuals immediately.

Ich (Ichthyophthirius multifiliis): White spots on body and fins. Treatable with temperature elevation to 28–30°C and appropriate medication.

Velvet (Oodinium): Fine golden dust on body - treat promptly in a hospital tank.

Poor water quality: The most common cause of recurring illness. A fully cycled tank and weekly water changes are the most effective disease prevention.