X-Ray Tetra Care Guide: See-Through Beauty for Community Tanks

Table of Contents

• Introduction
• Species Overview and Origin
• Tank Setup and Water Parameters
• Feeding and Diet
• Behaviour and Temperament
• Compatible Tank Mates
• Breeding X-Ray Tetras
• Frequently Asked Questions
• Conclusion

Introduction

Few freshwater fish can match the quiet elegance of a translucent body shimmering under aquarium lights. This x-ray tetra care guide covers everything you need to know about Pristella maxillaris, a hardy, peaceful schooling fish that is perfect for community tanks in Singapore. Whether you are setting up your first planted aquarium in an HDB flat or adding a new species to an established aquascape, the x-ray tetra is a reliable and visually captivating choice.

At Gensou, located at 5 Everton Park, we have been advising hobbyists on species selection for more than 20 years. The x-ray tetra consistently ranks among our top recommendations for beginners and experienced aquarists alike.

Species Overview and Origin

The x-ray tetra (Pristella maxillaris), also known as the pristella tetra or water goldfinch, is the sole member of its genus. It is native to the coastal rivers and brackish waters of Venezuela, Guyana, Suriname and Brazil. Its most striking feature is the translucent body through which the internal organs and spine are clearly visible — hence the common name.

Key Taxonomic Facts

• Scientific name: Pristella maxillaris (Ulrey, 1894)
• Family: Characidae
• Common names: X-ray tetra, pristella tetra, water goldfinch
• Maximum size: 4–5 cm
• Lifespan: 4–5 years
• Origin: Northern South America (Venezuela, Guyana, Suriname, Brazil)

The dorsal and anal fins feature bold black, yellow and white banding that adds a splash of colour to the otherwise transparent body. A gold variant is also available in the trade, bred selectively for a more opaque golden hue.

Tank Setup and Water Parameters

The x-ray tetra is one of the most adaptable tetras in the hobby, tolerating a wide range of water conditions. This flexibility makes it especially well suited to Singapore, where PUB tap water can vary slightly depending on your area.

Recommended Water Parameters

Tank Size and Layout

A school of six to eight x-ray tetras needs a minimum of 60 litres. For a larger group of 12 or more — which produces a far more impressive display — aim for 90–120 litres. These dimensions are still very manageable in most HDB living rooms or bedrooms.

Aquascaping Tips

• Substrate: Fine gravel or aquasoil. Both work well; aquasoil benefits planted setups.
• Plants: Mid-ground and background plants such as Rotala rotundifolia, Hygrophila polysperma and Vallisneria provide cover. Leave open swimming areas in the centre.
• Hardscape: Driftwood and smooth stones create natural boundaries and visual interest.
• Filtration: A hang-on-back filter or small canister filter with moderate flow. X-ray tetras are comfortable in gentle to moderate current.
• Lighting: Moderate lighting brings out the translucent body and fin colouration beautifully. Avoid extremely bright setups unless balanced by floating plant cover.

Singapore Tap Water Considerations

Unlike many soft-water tetras, the x-ray tetra can handle the slightly alkaline, moderately hard water that comes from PUB treatment works. This means less fussing with RO water or chemical buffers. Simply dechlorinate and you are good to go for most setups.

Feeding and Diet

X-ray tetras are omnivores and unfussy eaters — a welcome trait for busy hobbyists. In the wild, they feed on small insects, worms, crustaceans and plant matter.

Recommended Foods

• Staple: High-quality micro pellets or tropical flake food. Choose a brand with whole fish or shrimp as the first ingredient.
• Live foods: Daphnia, baby brine shrimp and micro worms. These encourage natural foraging behaviour and enhance colouration.
• Frozen foods: Frozen bloodworms, brine shrimp and cyclops — all widely available at Singapore aquarium shops.
• Vegetable supplement: Blanched spinach or spirulina-based flakes occasionally round out the diet.

Feed small amounts twice daily. In Singapore’s warm climate, uneaten food decomposes rapidly, so remove leftovers promptly to maintain water quality.

Behaviour and Temperament

The x-ray tetra is a peaceful, mid-dwelling schooling fish. It spends most of its time swimming in a loose group through the middle water column, occasionally exploring the upper reaches at feeding time.

Behavioural Highlights

• Schooling instinct: Keep a minimum of six individuals. In smaller groups, they become nervous and may hide constantly. A group of 10 or more produces the most natural, confident behaviour.
• Activity level: Moderately active during the day. They tend to rest quietly at night.
• Aggression: Virtually none. Occasional harmless chasing within the school is normal and establishes a subtle hierarchy.
• Hardiness: Exceptionally hardy once acclimatised. They tolerate minor fluctuations in water parameters better than many other tetra species.

Compatible Tank Mates

The x-ray tetra’s gentle disposition makes it compatible with a long list of community fish. Stick to species of a similar size and temperament for the best results.

Good Tank Mates

• Other small tetras (neon tetras, ember tetras, rummy-nose tetras)
• Rasboras (harlequin rasbora, chilli rasbora)
• Corydoras catfish
• Otocinclus catfish
• Small peaceful gouramis (honey gourami, sparkling gourami)
• Amano shrimp and Neocaridina shrimp
• Nerite and Malaysian trumpet snails

Tank Mates to Avoid

• Large or aggressive cichlids
• Predatory fish such as arowanas or large catfish
• Fin-nipping species like serpae tetras or tiger barbs
• Very large or boisterous fish that cause stress

Breeding X-Ray Tetras

X-ray tetras are egg scatterers and can be bred in captivity with a bit of preparation. Singapore’s warm temperatures naturally support the breeding process.

Breeding Setup

1. Conditioning: Feed the breeding group (ideally 3 males and 3 females) with live and frozen foods for 1–2 weeks. Females will become noticeably rounder as they develop eggs.
2. Breeding tank: Set up a separate 30–40 litre tank with slightly acidic water (pH 6.0–6.5), a temperature of 26–28 °C and dim lighting. Line the bottom with spawning mops or fine-leaved plants like Java moss.
3. Spawning trigger: A partial water change with slightly cooler water (1–2 °C below normal) often triggers spawning at dawn.
4. Egg laying: Females scatter 300–400 adhesive eggs among plants or spawning mops. The eggs are small, clear and slightly sticky.
5. Post-spawning: Remove the adults immediately — they will eat the eggs if given the chance.
6. Hatching: Eggs hatch in 24–36 hours. Fry become free-swimming after another 3–4 days. Feed infusoria or liquid fry food initially, then baby brine shrimp once they are large enough.

Tips for Success

• Keep the breeding tank dimly lit, as eggs and fry are sensitive to bright light.
• Use a sponge filter to avoid sucking up fry.
• Maintain impeccable water quality with small, frequent water changes.

Frequently Asked Questions

How many x-ray tetras should I keep together?

A minimum of six, but 10–12 is much better. Larger groups reduce stress, encourage natural schooling behaviour and create a far more striking visual display. In a 90-litre planted tank, a school of 12 is perfectly manageable.

Are x-ray tetras suitable for beginners in Singapore?

Absolutely. Their wide tolerance for water parameters — including the slightly alkaline, moderately hard PUB tap water — makes them one of the easiest tetras to keep. They are forgiving of minor mistakes and adapt quickly to new environments.

Can x-ray tetras live with shrimp?

Yes, adult Amano and Neocaridina shrimp are generally safe. However, very small shrimplets may be picked off. If you want to maintain a thriving shrimp breeding colony alongside x-ray tetras, provide dense moss cover such as Java moss or Christmas moss for the shrimplets to hide in.

Why do my x-ray tetras look pale?

Pale colouration is usually a sign of stress. Common causes include a tank that is too bright, insufficient hiding spots, a school that is too small, or poor water quality. Check your parameters, add more plants for cover and ensure you have at least six fish in the group.

Related Reading

• Bentosi Tetra Care Guide: Ornate Fins and Subtle Elegance
• Black Neon Tetra Care Guide: Understated Elegance
• Long-Fin Black Neon Tetra Care Guide: Flowing Dark Elegance
• Black Phantom Tetra Care Guide: Dark Elegance in Schools
• Black Skirt Tetra Care Guide: Bold Shape and Easy Keeping

Conclusion

The x-ray tetra is the kind of fish that quietly becomes the star of a community tank. Its transparent body catches the light in fascinating ways, it schools beautifully and it gets along with virtually everything. For Singapore hobbyists, its tolerance for local water conditions is a major bonus — no RO water, no pH adjusters, just straightforward fishkeeping.

Looking to add a school of x-ray tetras to your setup? Gensou has been the go-to aquascaping specialist in Singapore for over 20 years. Drop by our studio at 5 Everton Park, check out our online shop for fish, plants and supplies, or contact us for personalised advice. If you are planning a new aquascape from scratch, explore our custom aquarium service — we will design a tank that makes every species shine.