Glowlight Tetra
Glowlight Tetra (Hemigrammus erythrozonus)
Species: Hemigrammus erythrozonus
Origin: Guyana, South America
Size: 3–4 cm (1.2–1.6 in)
Shape: Slender, translucent body with a bright orange-red “glow” stripe along the side
Lifespan: 2–4 years
Temperament: Peaceful schooling fish (keep in groups of 6+)
Tank Level: Mid-water swimmer
Water Conditions:
- Temp: 24–28°C (75–82°F)
- pH: 5.5–7.5
- Soft to slightly hard water
Diet: Omnivore – flakes, micro pellets, frozen/live foods
Setup: Planted tank, dim lighting, gentle flow
Compatibility: Ideal community fish with other small peaceful species
Glowlight Tetra (Hemigrammus erythrozonus)
Species: Hemigrammus erythrozonus
Origin: Essequibo River basin, Guyana (South America)
Growth Form: Small, slender-bodied schooling tetra with a translucent silver body and a distinctive glowing orange-red stripe running from head to tail, resembling a neon light. Fins are delicate and mostly transparent with subtle hints of red or clear tones.
Size: Typically 3–4 cm (1.2–1.6 inches) when fully grown
Lifespan: Around 2–4 years in well-maintained aquarium conditions
Water Parameters:
- Temperature: 24–28°C (75–82°F)
- pH: 5.5–7.5 (slightly acidic to neutral preferred)
- Soft to moderately soft water preferred
Temperament: Peaceful, shy schooling fish. Best kept in groups of 6–10 or more to reduce stress and bring out natural behavior.
Tank Level: Middle water column swimmer
Diet: Omnivorous
- Micro pellets
- High-quality flakes
- Frozen/live foods (daphnia, brine shrimp, bloodworms)
Aquarium Setup:
- Heavily planted tanks preferred
- Dark substrate enhances coloration
- Floating plants help reduce stress
- Gentle filtration (they dislike strong currents)
Compatibility: Excellent community fish; pairs well with other peaceful species like rasboras, small tetras, corydoras, and dwarf gouramis.
Fun Facts
- The glowing stripe is a natural pigmentation that becomes more vivid under low lighting conditions.
- They are often mistaken for neon tetras but are slightly more slender and have a single glowing stripe instead of two distinct lines.
- Their “glow” effect inspired the name and made them popular in planted aquascapes.
- They were first introduced to the aquarium trade in the 1930s and remain a classic beginner-friendly tetra.