Silver Tetra Care Guide: Tank Setup, Diet, Tank Mates, and More

Table of Contents

• Key Takeaways
• Species Overview
• Classification
• Origin & Natural Habitat
• Appearance & Identification
• Average Size & Lifespan
• Care Guide
• Tank Mates
• Food & Diet
• Breeding & Reproduction
• Common Health Issues
• Common Mistakes to Avoid
• Where to Buy
• Frequently Asked Questions
• Closing Thoughts
• Recommended Video
• References

The silver tetra is one of those species that has been around in the hobby for a very long time but rarely gets the spotlight. It’s a robust, easy-to-keep fish with a clean silvery body that picks up iridescent highlights under good lighting. While it doesn’t have the flashy coloration of some of its relatives, the silver tetra makes up for it with hardiness, personality, and a level of adaptability that beginners will appreciate.

Native to the coastal rivers and streams of northeastern South America, this species has been in the aquarium trade since the early 1900s. It’s a solid community fish that works well in mid-sized to larger tanks, and it’s one of the more forgiving tetras when it comes to water parameters. Here’s everything you need to know about keeping them.

Key Takeaways

• Hardy and beginner-friendly with a wide tolerance for water conditions
• Active schooling fish that does best in groups of 6 or more
• Grows to about 3 inches, so needs at least a 30-gallon tank
• Omnivorous and easy to feed with no special dietary requirements
• Long-established in the hobby with captive-bred stock widely available

Species Overview

Field	Details
Scientific Name	Ctenobrycon spilurus
Common Names	Silver Tetra
Family	Characidae
Origin	Guyana, Suriname, French Guiana, Trinidad, Venezuela, lower Amazon
Care Level	Easy
Temperament	Peaceful (can be nippy in small groups)
Diet	Omnivore
Tank Level	Mid
Maximum Size	3.2 inches (8 cm)
Minimum Tank Size	30 gallons (114 liters)
Temperature	72-82°F (22-28°C)
pH	6.0-8.0
Hardness	5-20 dGH
Lifespan	5-8 years in captivity
Breeding	Egg scatterer
Breeding Difficulty	Easy to Moderate
Compatibility	Community
OK for Planted Tanks?	Yes (may nibble soft plants)

Classification

Taxonomic Level	Classification
Order	Characiformes
Family	Characidae
Subfamily	Stethaprioninae
Genus	Ctenobrycon
Species	C. spilurus (Valenciennes, 1850)

Ctenobrycon spilurus was originally described by Valenciennes in 1850. The genus name comes from the Greek “cteno” (comb) and “brycon” (a type of fish), referring to the comb-like teeth. This species has been shuffled between genera over the years but is now firmly placed in Ctenobrycon.

Note on family placement: Ctenobrycon is placed in the subfamily Stethaprioninae within Characidae. It was not affected by the 2024 Melo et al. phylogenomic revision and remains in the core Characidae.

Origin & Natural Habitat

The silver tetra has a broad native range across northeastern South America. It’s found in Guyana, Suriname, French Guiana, Trinidad, Venezuela, and the lower Amazon basin in Brazil. This wide distribution contributes to its adaptability in aquarium conditions, as wild populations have adapted to a variety of water types across their range.

In the wild, silver tetras inhabit slow-moving rivers, streams, and floodplain pools with varying water conditions from clear to slightly turbid. They’re often found in areas with moderate vegetation and are tolerant of a wider range of pH and hardness than many South American tetras. They tend to congregate in open areas where they school in the mid-water column.

The species has also been introduced to waters outside its native range, including parts of the United States (Florida and Hawaii), where feral populations have established. This speaks to its adaptability and resilience.

Appearance & Identification

The silver tetra has a deep, laterally compressed body that gives it a more rounded profile than many other tetras. The body is predominantly silvery with a bright metallic sheen that catches the light beautifully. Under good conditions, you’ll notice subtle hints of yellow and green iridescence across the scales.

The fins are mostly transparent with a slight yellowish tinge. A small dark spot is present at the base of the caudal fin (the “spilurus” in the scientific name refers to this spotted tail). The eye is large and has a reddish upper rim that adds a touch of color to the face.

Sexual dimorphism becomes apparent in mature fish. Males are slimmer and slightly more colorful, with a more pronounced iridescent sheen. Females are noticeably fuller-bodied, especially when carrying eggs, and tend to grow slightly larger.

Average Size & Lifespan

Silver tetras grow to about 3.2 inches (8 cm), making them a mid-sized tetra. They’re larger than species like neons or embers but still well within community tank territory. Their deep body shape makes them look bigger than their length suggests.

With proper care, expect a lifespan of 5 to 8 years. This is a long-lived species by tetra standards, and their hardiness means they often reach the upper end of that range even for less experienced keepers.

Care Guide

Tank Size

A 30-gallon tank is the minimum for a group of silver tetras. Their larger size and active swimming habits mean they need more room than smaller tetra species. For a school of 8 to 10 with other community fish, a 40-gallon breeder or 55-gallon tank is more appropriate and gives the school enough space to move freely.

Water Parameters

Parameter	Ideal Range
Temperature	72-82°F (22-28°C)
pH	6.0-8.0
General Hardness	5-20 dGH
KH	3-12 dKH
Ammonia / Nitrite	0 ppm
Nitrate	Below 30 ppm

One of the biggest advantages of the silver tetra is its flexibility with water parameters. Unlike many South American tetras that demand soft, acidic water, silver tetras do well across a broad range. They’ll thrive in soft blackwater setups just as readily as in moderately hard, neutral water straight from the tap. This makes them an excellent choice for beginners or anyone who doesn’t want to fuss with RO water and remineralization.

Weekly water changes of 25 to 30 percent keep nitrates in check and maintain good water quality. Their tolerance is wide, but consistency is still important.

Tank Setup

Silver tetras appreciate a mix of open swimming space and planted areas. They’re mid-water swimmers that spend most of their time in the open, so don’t overcrowd the tank with hardscape and plants. A well-planted background and sides with a clear center works well.

Standard aquarium lighting is fine. A dark substrate helps show off their silvery coloration. Sand or fine gravel both work. Driftwood and rocks can provide visual interest and some cover, but these fish don’t require hiding spots the way more timid species do.

One note on plants: silver tetras may nibble on soft-leaved plants like Cabomba or Elodea, especially if their diet lacks plant matter. Hardy plants like Java fern, Anubias, and Vallisneria hold up better.

Tank Mates

Silver tetras are generally peaceful community fish, though they can occasionally nip at long-finned tank mates, especially if kept in groups that are too small. A group of 6 or more keeps this behavior in check.

Good Tank Mates

• Other medium-sized tetras (black skirt, pristella, bloodfin)
• Corydoras catfish
• Bristlenose and rubber lip plecos
• Rainbowfish
• Peaceful barbs (cherry barbs, gold barbs)
• Gouramis (pearl, honey, blue)
• Medium-sized rasboras
• Loaches (kuhli, yo-yo)

Tank Mates to Avoid

• Long-finned species (bettas, fancy guppies, angelfish) due to potential nipping
• Very small fish or shrimp that might be harassed
• Large aggressive cichlids

Food & Diet

Silver tetras are true omnivores that eat just about anything offered. They’re enthusiastic feeders with hearty appetites.

• Staple: High-quality flake food or pellets
• Frozen foods: Bloodworms, brine shrimp, daphnia
• Live foods: Brine shrimp, daphnia, blackworms
• Vegetable matter: Spirulina flakes, blanched spinach, zucchini

Including some plant-based foods in their diet is important. Without it, they’re more likely to snack on aquarium plants. Feed two to three times daily in amounts they can consume within a few minutes. These fish can be greedy, so watch that they don’t outcompete slower tank mates at feeding time.

Breeding & Reproduction

Silver tetras are one of the easier tetras to breed in captivity. They’re prolific egg scatterers that will spawn readily under the right conditions.

Breeding Setup

• Breeding tank: 15 to 20 gallons
• Water: Slightly acidic (pH 6.0-6.5), soft to moderately soft, temperature 78-80°F
• Decor: Fine-leaved plants or spawning mops, a mesh bottom to protect eggs
• Filtration: Gentle sponge filter
• Lighting: Dim, or cover the tank to reduce light

Condition breeding pairs or groups with plenty of live and frozen foods for a week or two before spawning attempts. Spawning usually occurs in the morning. Females can scatter several hundred eggs among plants or over the substrate. Remove adults after spawning, as they will readily eat the eggs.

Eggs hatch in about 24 to 36 hours, and fry become free-swimming within 3 to 4 days. Feed fry infusoria or liquid fry food initially, then transition to baby brine shrimp. Growth is relatively quick compared to many tetra species.

Common Health Issues

• Ich: Can occur during acclimation or after temperature changes, though silver tetras are more resistant than many delicate tetras.
• Fin rot: Usually caused by poor water quality or stress. Responds well to improved conditions and, in severe cases, antibacterial treatment.
• Obesity: These are enthusiastic eaters. Overfeeding is a real risk, leading to fatty liver and shortened lifespan. Feed measured portions.
• Internal parasites: Occasionally seen in wild-caught specimens. Quarantine and prophylactic treatment are recommended for new arrivals.

Common Mistakes to Avoid

• Keeping too few: Small groups of 3 or 4 silver tetras can become nippy. Keep at least 6, preferably 8 or more, to spread any minor aggression within the school.
• Tank too small: Their size and activity level mean they really do need that 30-gallon minimum. Cramped quarters lead to stress and fin nipping.
• Overfeeding: They’ll eat everything you give them and beg for more. Stick to measured portions and include fasting days.
• Pairing with long-finned fish: The occasional fin nipping tendency means bettas, fancy guppies, and angelfish are not ideal tank mates.
• Ignoring plant-based foods: Without vegetable matter in their diet, they’ll supplement by eating your plants.

Where to Buy

Silver tetras are not as commonly stocked as some other tetras, but they can be found through specialty online retailers. Check these trusted sources:

• Flip Aquatics
• Dan’s Fish

Frequently Asked Questions

Are silver tetras aggressive?

Not truly aggressive, but they can be fin nippers if kept in small groups or in cramped tanks. A school of 6 or more in an appropriately sized tank keeps this behavior manageable. Avoid pairing them with slow-moving, long-finned species to be safe.

How big do silver tetras get?

They reach about 3.2 inches (8 cm), with females growing slightly larger than males. Their deep, compressed body shape makes them appear larger than their length alone suggests.

Can silver tetras live with shrimp?

Adult Amano shrimp are generally fine, but smaller shrimp species like cherry shrimp may be harassed or eaten, especially young shrimplets. If you want to keep a breeding shrimp colony, silver tetras are not the best choice for tank mates.

Closing Thoughts

The silver tetra won’t win any awards for flashy coloration, but it has earned its place in the hobby through sheer reliability. It’s hardy, easy to feed, tolerant of a wide range of water conditions, and breeds without much difficulty. For anyone looking for a mid-sized community tetra that doesn’t demand special water chemistry or a complicated diet, the silver tetra is hard to beat.

A school of these fish in a well-maintained tank has a clean, elegant look. The way their silvery scales catch and reflect light as they move together through the water is understated but genuinely attractive. Sometimes the best fish aren’t the flashiest ones. They’re the ones that just work.

Recommended Video

Check out our Tetra Tier List video where we rank popular tetra species for the home aquarium:

References

• Froese, R. and D. Pauly, Eds. FishBase. Ctenobrycon spilurus. Accessed 2025.
• SeriouslyFish. Ctenobrycon spilurus species profile. Accessed 2025.
• Melo, B. F., et al. (2024). Phylogenomics of Characidae. Molecular Phylogenetics and Evolution.

Explore More Tetras

The silver tetra is just one of dozens of characin species we cover in our complete species directory. Whether you’re into hardy community fish or rare specialty tetras, our guide has you covered.

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