
Glow Light Tetra
Hemigrammus erythrozonus

Glow Light Tetras exhibit a slender, translucent body with vibrant iridescent blue and green hues, marked by a prominent orange stripe along the side.
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About the Glow Light Tetra
The Glowlight Tetra (Hemigrammus erythrozonus) is a small, peaceful South American schooling tetra with a translucent silvery body and a distinctive iridescent orange-red stripe running from the snout to the base of the tail.
Quick Facts
Size
1.5 inches
Temperament
Peaceful
Difficulty
Beginner
Min Tank Size
10 gallons
Lifespan
3-5 years
Origin
South America
Diet
Omnivore - accepts flakes, small live foods, and freeze-dried daphnia.
Water Parameters
22-28°C
5.5-7.5
3-12 dGH
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Calculate heater sizeCare Notes
- Glow Light Tetras prefer a planted tank environment with plenty of hiding spots and subdued lighting to mimic their natural habitat.
- Maintaining consistent water quality with a pH around 5.5-7.5 and a temperature range of 22-28°C (72-82°F) is recommended.
- Feed Glow Light Tetras a varied diet of high-quality flake foods, small pellets, as well as occasional live or frozen foods like brine shrimp and daphnia.
- These tetras are peaceful and social fish that thrive in groups of at least six; they can be housed with other non-aggressive, similarly sized species.
- Breeding can be achieved by creating a separate breeding tank with softer, slightly acidic water and substrate to protect eggs from predation.
- Watch for common health issues such as ich, a parasitic infection, indicated by white spots on their bodies, and ensure rapid treatment if symptoms arise.
- Regular water changes and a well-maintained filtration system are crucial to prevent the build-up of harmful toxins like ammonia and nitrate.
Compatibility
Good Tankmates
- Other peaceful community fish
- Small tetras and rasboras
- Corydoras catfish
- Peaceful dwarf cichlids such as Apistogramma
- Some shrimp (use caution with dwarf shrimp and shrimplets)
Avoid
- Aggressive cichlids
- Large predatory fish like Oscars
- Fin-nipping species like Tiger Barbs
- Large, territorial fish such as some Arowanas
Habitat and Natural Environment
Glow Light Tetras (Luminichthys noctifera) are native to the blackwater streams and tributaries of South America. They thrive in slow-moving waters with a dense canopy overhead that diffuses sunlight, mimicking the dimly lit conditions of their natural habitat.
To closely replicate their natural environment, provide plenty of plants, driftwood, and leaf litter in their tank.
Tank Setup Requirements
Glow Light Tetras are adaptable and can thrive in a variety of tank setups, making them ideal for beginner aquarists.
- Tank Size: A minimum of 10 gallons is recommended for a small school.
- Water Temperature: Maintain between 72°F and 78°F.
- pH Level: Aim for a pH level between 6.0 and 7.0.
- Substrate: Use a dark substrate to enhance their glowing colors.
Adding floating plants can help diffuse light and create a more natural setting for your Glow Light Tetras.
Feeding and Diet
These tetras are omnivorous and enjoy a diverse diet. In the wild, they feed on small invertebrates and plant matter. In captivity, they thrive on a diet that includes high-quality flake foods, pellets, and live or frozen foods.
- Flake or Pellet Food: Provide a staple diet of high-quality tropical fish flakes or micro pellets.
- Live or Frozen Foods: Supplement their diet with daphnia, brine shrimp, and bloodworms.
Feed small amounts once or twice daily, ensuring no excess food is left to prevent water quality issues.
Behavior and Temperament
Glow Light Tetras are peaceful schooling fish that do best in groups of six or more. They are active swimmers and do well in community tanks with similarly sized, non-aggressive species.
- Social Behavior: Schooling fish, prefer groups.
- Compatible Tank Mates: Corydoras, other tetras, and small rasboras.
Avoid housing Glow Light Tetras with larger, aggressive fish that may view them as prey.
Breeding
Breeding Glow Light Tetras can be rewarding as they are egg scatterers. They require slightly acidic water to spawn effectively.
- Spawning Tank: Set up a separate breeding tank with a temperature around 78°F.
- Substrate: Use fine-leaved plants or a spawning mop for eggs to cling to.
- Parental Care: Remove adults post-spawning to prevent them from eating the eggs.
Fry can be fed infusoria or commercially available fry foods once hatched.
Health and Common Issues
Glow Light Tetras are generally hardy but can be susceptible to common freshwater fish diseases if water conditions are not well maintained.
- Ich: Look for white spots on the body and fins.
- Fin Rot: Signs include fraying fins and a lack of appetite.
Regular water changes and maintaining optimal water parameters are crucial for preventing disease.
Observing your fish regularly will help you detect and treat any health issues promptly.
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