Golden pristella tetra (Pristella maxillaris) care guide

Group
Freshwater fish
Other names
Pristella tetra, Water goldfinch, X-ray fish, Golden pristella (semi-albino form), Pristella riddlei
Family
Acestrorhamphidae (American tetras; formerly Characidae)
Origin
Coastal river drainages of Venezuela, Guyana, Suriname, French Guiana and northern Brazil, plus parts of the Amazon and Orinoco basins.
Water
freshwater
Maximum size
4.5 cm
Temperature
22–28°C
pH
6–7.5
Hardness
Soft to hard, 2–20 dGH
Minimum tank
54 litres
Care level
beginner
Temperament
peaceful

Care

The X-ray tetra is a hardy, easy-going little shoaler and one of the most reliable tetras for a first community tank. Keep at least six, and ideally ten or more – a bigger group is calmer, more confident and much better to watch, with males displaying to one another. A tank with a base of about 60 × 30 cm is enough. It looks its best in a well-planted aquarium with a dark sandy substrate, some driftwood and a few dried leaves, and appreciates fairly dim lighting or floating plants to diffuse it. Its translucent body shows off well against a dark background. It is unusually tolerant of water chemistry: anything from soft to fairly hard (roughly 2–20 dGH), pH about 6.0–7.5 and temperatures of 22–28 °C. Wild populations even turn up in slightly brackish coastal water, though freshwater is all it needs. Almost every fish on sale is commercially bred in the Far East or Eastern Europe, so stock is robust; just keep the water clean with regular partial changes. Listed as Least Concern by the IUCN, and nearly all X-ray tetras sold are captive bred, mostly in Eastern Europe. Sources: Seriously Fish (seriouslyfish.com/species/pristella-maxillaris/); FishBase (fishbase.se/summary/Pristella-maxillaris.html); Wikipedia (en.wikipedia.org/wiki/Pristellamaxillaris). Checked October 2026.

Diet

A micropredator that eats small insects, worms and crustaceans in the wild. In the aquarium it takes good dried flakes and granules happily, but give it small live and frozen foods such as daphnia and brine shrimp several times a week for the best colour and condition.

Breeding

An egg-scatterer with no parental care, which will spawn in a group or in pairs. Females are larger and noticeably plumper than males. Use a separate breeding tank with dim lighting, soft acidic water (pH 5.5–6.5, 1–5 dGH) at around 26.5–29 °C, and fine-leaved plants, spawning mops or mesh over the base so the eggs fall out of the adults' reach. Condition the fish well on live and frozen foods first. Remove the adults after spawning, as they will eat the eggs. Fry need infusoria-type food at first, then brine shrimp nauplii and microworm. A semi-albino golden form is also line-bred.

Compatibility and tank mates

A very peaceful fish that does well with other small South American species and in general communities of small fish – other tetras, pencilfish, rasboras, Corydoras, small catfish and dwarf cichlids. Avoid boisterous or much larger tankmates that will bully it or swallow it.

Last updated 4 October 2026. Community-edited care guide on Aquatic-Auctions.

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