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Tetra Fish But with more than 150 known species and thousands of possible colors, selecting the right tetra can be daunting.
In this guide, we’ll explore the world of tetra fish, from the popular neon tetra to the more exotic varieties like the emperor or Congo tetra.
You’ll learn about their care needs, ideal tank setups, compatibility with other fish, Tetra fish, and what makes each type special.
Let’s dive into the glimmering waters of tetra diversity and discover which of these tiny treasures is right for your tank.
Tetras 101—An Introduction
What Are Tetra Fish?
Tetras are typically
Small-sized: Most range from 1 to 2 inches.
Hardy: Great for beginner aquarists.
Social: Thrive in schools of 6 or more.
Colorful: They come in a wide array of hues and patterns.
Neon Tetras—The Classic Favourite
The Jewel of the Freshwater World
Neon tetras (Paracheirodon innesi) are perhaps the most identifiable tetra species.
Size: 1.5 inches
Lifespan: Up to 5 years
Water parameters: Soft, slightly acidic water (pH 6.0–7.0)
Temperature: 72–78°F (22–26°C)
In schools, they create stunning synchronised displays. Fun Fact:
Their colors dull at night or when stressed, but come back with full intensity when they’re healthy and happy.
Cardinal Tetras—Neon’s Brighter Cousin
Bold and Beautiful
On first impression, cardinal tetras (Paracheirodon axelrodi) can be mistaken for neons, but they possess a stripe running from head to tail that sets them apart.
Size: 2 inches
Lifespan: Up to 5 years
Ideal water: Soft, acidic (pH 5.0–6.5)
Temperature: 75–82°F (24–28°C)
Cardinals are ever so slightly more delicate than neons and prefer to inhabit mature, settled tanks with proper filtration and much plant cover.
They are a peaceful species and hence perfect for community tanks where they can live alongside other non-aggressive small fish.
Glowlight Tetras—Subtle and Elegant
Understated Beauty
Glowlight tetras (Hemigrammus erythrozonus) have an orange-red stripe on their dorsal surface that extends from the snout to the tail base. They have the rest of their body semi-transparent, giving them a glowing sheen when kept in soft light.
Size: 1.5 inches
Lifespan: 3–4 years
Water pH: 6.0–7.5
Temperature: 72–80°F (22–27°C)
They adore planted aquariums and low-light settings, bringing out the glowing effect on their stripe.
Ember Tetras—Fire in the Water
The Tiny Flame
Size: 0.75 inches
Lifespan: 2–4 years
pH: 5.5–7.0
Temperature: 73–84°F (23–29°C)
Embers prefer soft-light tanks with a dark bottom, which makes their color pop.
Ideal for nano tanks, they also make great tank mates for retiring species.
Black Skirt Tetras—Dramatic and Bold
A Statement Fish
Size: 2.5 inches
Lifespan: 5–7 years
pH: 6.0–7.5
Temperature: 70–82°F (21–28°C)
Rummy Nose Tetras—Nature’s Mood Rings
Indicators of Health
Size: 2 inches
Lifespan: 5–6 years
Water pH: 5.5–7.0
Temperature: 75–81°F (24–27°C)
Their brilliant red nose also acts as a health indicator—when stressed or ill, the red disappears. In well-conditioned tanks with excellent water quality, they are calm and quite strikingly lovely in action.
They do best in schools of 10 or more.
Congo Tetras—Regal and Exotic
African Royalty
Unlike their South American relatives, Congo tetras (Phenacogrammus interruptus) are African and larger, more showy fish.
Size: 3–4 inches
Lifespan: 4–6 years
pH: 6.0–7.5
Temperature: 73–82°F (23–28°C)
Males have long, flowing fins and iridescent scales that shimmer blue, gold, and green.
Because of their size, they need a bigger tank (30 gallons minimum) and should be kept in small harems (1 male to 2-3 females).
Lemon Tetras—Bright and Cheerful
A Splash of Citrus
Lemon tetras (Hyphessobrycon pulchripinnis) are easily overlooked, but their pale yellow color, red eyes, and black fin tips make them a charming addition.
Size: 1.5–2 inches
Lifespan: 4–5 years
pH: 6.0–7.5
Temperature: 72–82°F (22–28°C)
They are active swimmers who enjoy open space but also like plants and places to hide. When properly cared for, their lemon color deepens with age.
Penguin Tetras—Marching in Schools
Graceful and Unique
Penguin tetras (Thayeria boehlkei) have slender silver bodies and a clear black stripe running diagonally from mid-body to the lower tail fin.
Size: 2 inches
Lifespan: 4–6 years
pH: 5.5–7.5
Temperature: 73–81°F (23–27°C)
Their unusual swimming position—slightly upwards—is an added attraction to any tank. They are peaceful and laid-back, and they blend well in community tanks.
Emperor Tetras—Regal and Refined
True Sophistication
Royal Blue Emperor Tetras (Nematobrycon palmeri) are indeed living up to their name here with a slightly shimmering blue stripe, drape-like fins, and so on.
Size: 2 inches
Lifespan: 5 years
pH: 5.5–7.5
Temperature: 73–81°F (23–27°C)
Females are brighter in color with longer tails. They are easy-going, languid swimmers that thrive well in soft illumination and planted areas.
Best in peaceful community designs or biotope-type aquariums.
Caring for Tetras—Essentials for Success
Water Quality
Tetra Fish are ammonia- and nitrite-sensitive, so always cycle your tank prior to adding them. Most prefer
Soft, slightly acidic water
Stable temperatures
Regular water changes (25% weekly)
Diet
Tetras are omnivores and thrive on:
High-quality flakes or pellets
Frozen/live food: daphnia, brine shrimp, bloodworms
Occasional vegetables like blanched spinach
Tank Setup
Schooling space: Open swimming areas
Plants: Provide shelter and mimic natural habitat
Low lighting: enhances colors and reduces stress
Mixing and Matching—Best Tankmates
Tetra Fish are peaceful but best with similarly sized, non-aggressive fish. Excellent tankmates are:
Corydoras catfish
Small rasboras
Dwarf gouramis
Livebearers (like guppies or mollies)
Shrimp and snails
Conclusion
Whether you’re attracted to the traditional glow of a neon, the blazing vibrancy of an ember, or the imperial serenity of an emperor, there’s a tetra fish to suit your vision and tank aspirations. Their tranquil schooling behavior and dazzling colouration make them a pleasure to observe and a foundation of freshwater aquascaping.
Before making your selection, take into account
Tank size
Water parameters
Compatibility
Your preferred color scheme
Once you’ve selected your tetras, relax and enjoy the fascinating ballet of your new finned friends. One of the pleasures in the hobby is as fulfilling as a thriving, colorful school of tetra fish snaking through the dense underwater vegetation.
FAQs
How many tetras should I keep together?
Tetras are schooling fish and must be kept in quantities of at least 6 of the same sort. But the more that you keep (within reason and within tank confines), the worse they will misbehave and the more artificial their schooling appearance will be.
Can different types of tetra fish live together?
Yes, some tetra fsih species can peacefully be kept together in the same aquarium. Just make sure they need similar water parameters and temperaments. For instance, neon, ember, and glowlight tetras tend to get along together.
Are tetras good for beginners?
Yes. Most tetras, including the neon, black skirt, and glowlight tetras, are sturdy, resilient, and ideal for beginners. Just keep good water conditions and provide them with a balanced diet.
What is the lifespan of a tetra fish?
The majority of tetras live for three to five years on average, but with proper care, clean water, and a stress-free lifestyle, some can live up to seven years.
What do tetras eat?
Tetra Fish are omnivores. They like:
micro-pellets or flakes of high quality
Frozen or live foods (brine shrimp, bloodworms)
occasional vegetables blanched
A varied diet ensures health and vibrant color.
How do I know if my tetra fish is healthy?
A healthy tetra fish is
Active and socialising with others
Brightly colored
Eating regularly
Not hiding or breathing heavily
Faded color or isolation may indicate stress, poor water quality, or illness.
