Glowlight Tetra Complete Care Guide: Hemigrammus erythrozonus

Glowlight tetras are the quietly beautiful alternative to cardinal and neon schools — a soft red-gold stripe across a translucent body that seems to float in dim blackwater. This glowlight tetra complete care guide covers Hemigrammus erythrozonus from tank requirements through feeding, breeding and the shops that stock it in Singapore. Written by the team at Gensou Aquascaping, 5 Everton Park, with over 20 years of hands-on experience stocking planted tetra communities.

Species Profile

Hemigrammus erythrozonus originates from the Essequibo River drainage of Guyana — blackwater streams under dense forest canopy with soft, acidic water. Adult size is 3.5-4 cm with females running slightly plumper. The glow is a red-gold lateral stripe bordered by a translucent silver body, with matching orange tips on the dorsal and caudal fins. Lifespan in a stable tank is four to five years.

Tank Size and Schooling

Minimum tank is 60 litres for a school of eight, 90 litres ideal for twelve. Glowlights are mid-level swimmers forming loose schools that tighten when startled. Tank length 60-75 cm is plenty — this species does not pace long corridors the way rummy-nose do. They sit happily in nano-to-small community tanks where cardinals or rummy-nose would feel cramped. Browse the aquarium tanks and cabinets range for 60 cm rimless options.

Water Parameters

Temperature 24-28 degrees Celsius, pH 5.8-7.2, GH 2-8, KH 0-4. More tolerant of parameter drift than rummy-nose or cardinal tetras, which makes glowlights a good choice for keepers still learning to stabilise a blackwater tank. Singapore tap water works post-dechlorination; an aquasoil substrate brings pH into the preferred lower range. Nitrate under 20 mg/L for best colour.

Tank Setup

A dim planted tank with driftwood, catappa leaves and a dark substrate shows glowlights at their best. The red-gold stripe practically fluoresces against a tannin-stained backdrop. Hardscape with two medium pieces of Malaysian driftwood or spider wood, seeded with anubias and java fern. Source substrate from the decoration and substrate range — active aquasoil is preferable to inert sand for this species.

Planting

Background stems (Rotala, Ludwigia, Hygrophila), midground crypts (Cryptocoryne wendtii, parva, undulata), and a floor of java moss or Monte Carlo. Floating frogbit or salvinia on 30-40 per cent of the surface. Glowlight tetras look their best under dappled light filtered through floating plants rather than bright open lighting. Visit the live plants range for stem plant selections.

Filtration and Flow

Canister filter at 4x tank volume per hour, or a large sponge filter on a good air pump for a 60-litre setup. Gentle to moderate flow — spray bars aimed at the rear glass rather than direct jets into the swimming zone. Prefilter sponge on the intake prevents juvenile glowlights getting sucked up during any accidental spawn. Browse the filtration range.

Feeding

Micro pellets (Hikari, Tropical), crushed flake, frozen bloodworm (chopped for smaller individuals), daphnia, cyclops and brine shrimp. Two small feedings a day, one fasting day per week. Glowlights are unfussy eaters and take prepared foods readily from day one — unusual among tetras which often prefer live foods initially. Pick up micro pellets from the fish food and feeding range.

Tank Mates

Peaceful and excellent community members. Mix with ember tetras, rummy-nose, cardinal tetras, Apistogramma, pygmy corydoras, otocinclus, nerite snails and neocaridina shrimp (adults; juveniles may be eaten). Avoid fin-nipping tetras like serpae and black widow, large gouramis over 10 cm, and all aggressive cichlids. A mixed blackwater community with three tetra species and a bottom-dweller layer is where glowlights shine.

Breeding

Egg-scatterers requiring very soft acidic water (GH under 2, pH 6.0-6.5). A 20-litre breeding tank with a moss mat or spawning grate, a conditioned pair fed live daphnia for two weeks, dim lighting and stable 26 degrees Celsius will produce eggs within 48 hours. Remove adults immediately. Fry hatch at 24-36 hours, free-swim at day five, feed on infusoria then microworm and brine shrimp nauplii. Not especially difficult compared to most tetras.

Sourcing in Singapore

Glowlight tetras are stocked regularly at C328 Clementi (SGD 1-1.50 each), Iwarna (SGD 1.50-2 each), and Seaview. Stock is usually farm-bred from Southeast Asian breeders and arrives in reasonable condition. Occasionally available on Carousell from local breeders at SGD 2 each — these are often larger, better-coloured fish worth the small premium. A school of twelve costs SGD 12-24 depending on source, making this one of the most accessible tetra schools for a first blackwater tank.

Related Reading

• Tetra Fish Tank Complete Guide
• Tetra Fish Aquarium Setup Guide
• Ember Tetra Complete Care Guide
• Rummy Nose Tetra Complete Care Guide
• Cardinal Tetra Complete Care Guide