Glowlight Tetra
Hemigrammus erythrozonus
Description
The Glowlight Tetra is a small, vibrant fish known for its glowing red-orange stripe that runs from the middle of its body to its tail, giving it a “glow” effect, especially under aquarium lighting. This species has a slender, elongated body with a translucent silver to pale body coloration, and the red stripe makes them highly attractive in aquariums. The Glowlight Tetra is peaceful and social, often seen schooling together in the middle and upper parts of the tank. They are very active swimmers and thrive in groups, exhibiting charming, lively behavior.
Habitat Origin
Native to the Orinoco and Amazon basins in South America, particularly in Venezuela, Brazil, and Guyana. They inhabit slow-moving, clear waters with dense vegetation in their natural environment.
Aquarium
Ideal Number in Aquarium: At least 6 individuals, as they are schooling fish and feel more secure in groups.
Favorite Food
Glowlight Tetras are omnivores and will accept a variety of foods, including high-quality flake food, micro pellets, and live or frozen foods such as brine shrimp, daphnia, and bloodworms. They also appreciate plant matter, such as blanched spinach, algae, and fine plant-based foods.
Behavior:
Glowlight Tetras are peaceful, active fish that do well in community tanks with other small, non-aggressive species. They are schooling fish and feel safest when kept in groups of at least 6 individuals. These fish are generally calm but are quite active, swimming throughout the middle to upper areas of the tank. They are not fin-nippers and get along well with other peaceful tankmates. Due to their small size, they are best suited for aquariums with other small fish.
Special Care:
Glowlight Tetras thrive in a well-planted tank with plenty of hiding spots, such as plants, driftwood, and rocks. They appreciate stable water conditions, so regular water changes and a good filtration system are important. They do best in slightly acidic to neutral water conditions and prefer a calm environment with gentle water flow.
Compatibility with Other Fish:
Yes, Glowlight Tetras are excellent tankmates for other peaceful, small fish, such as other tetras, rasboras, and small shrimp. Avoid keeping them with large or aggressive species that may harm or intimidate them. Due to their small size, they should be housed with other small, non-aggressive fish.
Breeding Tank Setup
A separate breeding tank is strongly recommended for Glowlight Tetras to ensure egg and fry survival. They are egg scatterers, and adults will eat the eggs if left in a community tank. A 10-gallon tank (38 liters) is sufficient for a pair or small group, while a 20-gallon tank (75 liters) is better for multiple pairs. Maintain pH 6.0–7.0, temperature 24–28°C (75–82°F), and hardness 2–12 dGH. Use a sponge filter for safe, gentle water flow, and add plants like Java moss, Hornwort, or Anubias, which serve as spawning and hiding sites for eggs. Keep lighting moderate, with a 10–12 hour cycle to mimic natural conditions.
Conditioning the Breeders
Prepare the Glowlight Tetras by feeding a nutritious, varied diet of tropical flakes or pellets, live/frozen foods such as brine shrimp, daphnia, and bloodworms, and vegetable options like spinach or spirulina. This enhances their health and breeding readiness. Perform weekly water changes (25–30%) to keep conditions stable. Before spawning, simulate seasonal cues with a 50% water change and raise the temperature to 28°C (82°F) to encourage mating behavior.
Spawning Process
Spawning typically occurs in the early morning, often triggered by improved water conditions and temperature changes. Males display bright neon stripes and court the females, who release 20–50 sticky eggs onto plant leaves or tank surfaces, which are then fertilized. Immediately after spawning, remove the adult fish to prevent them from consuming the eggs. Leaving them in the tank risks significant egg loss.
Fry Development
Eggs hatch within 24–48 hours, depending on temperature. Fry absorb their yolk sacs for the first few days and then begin free-swimming. Start feeding with infusoria or liquid fry food, then gradually introduce baby brine shrimp, microworms, or finely crushed flake food. The fry will also benefit from biofilm and micro-particles found on live plants. Maintain clean water with small water changes (10–20%) daily or every two days, and keep the temperature steady within the ideal range.
Advanced Tips
Glowlight Tetras reach breeding age at 6–12 months, with males being smaller and more vibrant, and females rounder, especially when gravid. Avoid stressors such as sudden changes in water conditions or aggressive tank mates. Consistent filtration, temperature, and cleanliness are critical for healthy fry development. With proper care and attention to detail, breeding Glowlight Tetras can be a rewarding experience for both beginner and seasoned aquarists.