Pristella tetra

Quick facts

Adult size

4.5 cm

Lifespan

can live up to 5 years

Tank zone

mid

Temperament

peaceful

Difficulty

beginner

Schooling

recommended 6+ (critical minimum 5, thrives at 10+)

Water parameters

Temperature

22–28°C

pH

6.0 to 8.0

Hardness

2 to 20 dGH

Tank requirements

Minimum volume

75 L

Minimum length

60 cm

Flow

low

Lighting

dim preferred

Substrate

any

Driftwood

preferred

Hiding spots

needed

Feeding

Diet: omnivore, feeds primarily at the mid.

Eats anything. Flake, micro pellets, frozen bloodworm, frozen brine shrimp, frozen daphnia, live baby brine shrimp. Feeds in the midwater column. Not demanding, not competitive, not picky. A reliable feeder that will eat its share in any community. Twice daily in moderate amounts. Color in the fins improves with a varied diet that includes frozen food regularly. The yellow dorsal and anal fin markings are more vivid when the fish is well-fed and in good conditions.

Compatibility

• One of the most tolerant small tetras for varied water conditions. Pristella tetras handle hard alkaline water (up to pH 8, GH 20) without complaint, which makes them one of the few tetras suitable for keepers on hard tap water who don't want to run an RO unit.
• Peaceful schooling fish that works with any non-aggressive tankmate. Tetras, rasboras, corydoras, gouramis, and small cichlids are all fine. No nipping behavior.
• Groups of 6+ for proper schooling. In large groups (10+) the translucent body with yellow, black, and white fin markings is surprisingly attractive despite not having the flash of neons or cardinals.
• Also sold as the 'X-ray tetra' because the body is translucent enough to see the spinal column and swim bladder. The name oversells the transparency a bit but the effect is real under the right lighting.

Habitat

Native to coastal regions of South America: the Guianas (Guyana, Suriname, French Guiana), Venezuela, and the lower Amazon in Brazil. Found in a range of habitats from soft, acidic blackwater streams to hard, slightly brackish coastal waters. This dual habitat tolerance explains why the species handles such a wide range of water chemistry in captivity. The body is compressed and translucent silver with a subtle yellowish tint. The dorsal and anal fins have a distinctive tricolor pattern: yellow base, black middle band, and white tip. The caudal fin is pale red. In a well-maintained tank against a dark background, a school of pristella tetras looks better than most people expect from such a 'plain' fish. Males are slimmer; females are rounder when full of eggs. The species (Pristella maxillaris) was described by Ulrey in 1894 and has been in the hobby since the early 20th century. Commercially bred in vast quantities and inexpensive. One of the albino/gold variants is sold as the 'golden pristella' and lacks the dark markings, retaining only the yellow coloring.

Breeding

One of the more forgiving tetras to breed. Unlike many Amazon tetras, pristellas don't require ultra-soft acidic water. They'll spawn in moderately hard water (GH up to 15) that would prevent most Paracheirodon and Hyphessobrycon species from breeding. Condition a pair with frozen food for a week. Set up a breeding tank with fine-leaved plants or spawning mops, temperature at 25–27°C, and dim lighting. Spawning happens at dawn. The pair scatters 300-400 eggs among the plants. Eggs are non-adhesive and sink into plant material. Adults eat eggs, so remove them after spawning. Eggs hatch in 24-36 hours. Fry are tiny but not as small as neon tetra fry; they can take baby brine shrimp within 3-4 days of becoming free-swimming. Growth is steady. The tolerance for varied water conditions during breeding is the species' main advantage for hobbyist breeders.

Common problems

Hardy to the point of being boring. Serious health problems are rare. Ich appears in stressed new arrivals; standard treatment works. The species tolerates most medications without issue. The main 'problem' is cosmetic: pristella tetras look plain in poorly lit tanks with pale substrate. They need dark substrate, planted background, and warm-toned lighting to show their best. The fin markings wash out under cool white LEDs. This display-dependent attractiveness means they're consistently overlooked in store tanks, which is a shame because in the right setup they're one of the better schooling tetras available. Lifespan is 4-5 years. Old fish gradually lose fin color intensity.

Bioload

Bioload coefficient: 1.1 (slim tetra slightly larger than neon).

Bioload coefficients are calibrated against the neon tetra as the anchor (1.0). See the methodology page for the formula and how each value was derived.

Further reading

• How to cycle a fish tank
• Stocking ideas by tank size