Should I buy it?
Glowlight Tetra
Hemigrammus erythrozonus
A copper-striped schooler less sensitive than neons. Hardy in neutral water, accepts flake, and schools tightly with eight or more.
Glowlight Tetra tank mates · 60L tank size hub
peaceful · beginner care
Sources & confidencehigh · partially verified · beginner: excellent
Checked against several solid care sources that mostly agree. Numbers here are a careful starting point. Your tap water, tank size, and habits decide the rest. How we evaluate.
Best for: Community tanks 60L or more with peaceful tank mates and a school of eight. A good alternative to neons in harder water.
Avoid if: You keep cichlids, large gouramis, or anything that treats 4 cm fish as prey.
Common mistakeBuying four glowlights as a ‘sample school’ is how the stripe never shows. They need eight or more to school tightly; four fish scatter and look washed out. Budget for a real school up front, or wait — token numbers are a display idea, not a glowlight plan.
Top things that go wrong
- Group welfare — not a solo display fish. Plan at least **6** together for normal behaviour; smaller groups often mean stress, colour loss, or nipping depending on species.
- Shrimp & snails. Cherry shrimp and other dwarfs can coexist with peaceful small fish; baby shrimp are food for almost anything that finds them.
What most shops don't tell you
- 1.Myth: glowlight tetras colour up in any group size like a shop handful. Reality: the copper-neon glow needs a real school of roughly eight or more — four fish is a sample bag, not the species people buy photos of.
- 2.Buying three or four to start. Glowlight Tetra settles in a group of 6 or more. An understocked school sulks at the back of the tank and loses colour within a fortnight.
- 3.Keep six or more in stable water. The stripe dulls when KH drifts. Avoid any fish that can gape a 4 cm tetra.
About this species
Glowlight tetras are soft-water characins with an orange-red stripe running from nose to tail base. A classic mid-water schooler for Amazon-type communities. A school of eight or more shows the stripe and tighter formation than a group of four.
- Beckford Pencilfish60L min · same group, comparable tank size
- Black Neon Tetra60L min · same group, comparable tank size
- Bloodfin tetra60L min · same group, comparable tank size
- Cardinal Tetra60L min · same group, comparable tank size
- Green neon tetra60L min · same group, comparable tank size
- Lemon Tetra60L min · same group, comparable tank size
- Silver Tip Tetra60L min · same group, comparable tank size
- X-ray tetra60L min · same group, comparable tank size
- Amano Shrimpalso beginner peaceful, similar tank size
- Assassin Snailalso beginner peaceful, similar tank size
- Beckford Pencilfishalso beginner peaceful, similar tank size
- Black Neon Tetraalso beginner peaceful, similar tank size
- Black phantom tetraalso beginner peaceful, similar tank size
- Bloodfin tetraalso beginner peaceful, similar tank size
- Agassiz’s dwarf cichlid tank matesnames this fish as a conditional pairing — read the pair page conditions
- Black phantom tetra tank mateslists this fish among its safer mates
- Bloodfin tetra tank mateslists this fish among its safer mates
- Ember Tetra tank mateslists this fish as a safe and recommended mate
- Golden / Beckford's pencilfish tank mateslists this fish among its recommended pairings
Plan grid
Key limits are above. Here: pH band, swim level, bioload, and activity.
Swim zones
Care snapshot
Quick compare before you buy. Not a score of how “good” the fish is.
- Beginner ease82
- Peacefulness90
- Community fit83
- Small-tank fit100
- Hardiness76
- Energy54
Numbers are deterministic planning indices from Fishori fields — not a scientific score of your individual fish.
Example setups
Starting points only. Run the pair checker for every fish you add.
Rough 90L+ layout: one calm centrepiece, 8–12 small tetras/rasboras, 6–8 corydoras-type bottom fish — verify every name in the pair checker before buying.
Safer directions include: Dwarf Gourami, Ember Tetra, Harlequin Rasbora.
Prioritise 6+ of Glowlight Tetra in 60L+ with filtration sized for messy feeding — add only mates that already pass pair checks with this species.
Compatibility
Tank mates for Glowlight Tetra
Usually safer (engine GOOD): Dwarf Gourami, Ember Tetra, Harlequin Rasbora, Neon Tetra. Conditional (CAUTION — read the pair page before buying): Angelfish, Betta, Corydoras Catfish, Discus, Tiger Barb. Avoid (RISKY): Green Terror, Jack Dempsey, Oscar. Every name links to a live pair check — the lists are a shortlist, not a stocking plan.
Usually safer
Open a pair page with this fish as the starting point.
Needs planning
Read the blocking rule on each pair page before experimenting.
Usually avoid
Do-not-stock combinations on conservative hobby rules.
Compare with
Run a real pair check: Glowlight Tetra + Dwarf Gourami
- Try Dwarf Gourami — open the pair check.
- Try Ember Tetra — open the pair check.
- Try Harlequin Rasbora — open the pair check.
- Try Neon Tetra — open the pair check.
Behaviour and temperament
Glowlight tetras are peaceful midwater schoolers that stay calmer and brighter in honest numbers of eight or more. They do not police the tank or shred fins. Washout and scattering usually mean under-stocking or midwater competition, not a bad strain from the shop.
What sets them off
- Sudden crowding
- Poor water quality
Fin nipping: Not a habitual fin-nipper; stressed or crowded individuals can still test fins.
Predation: Not a predator toward similarly sized community fish; fry and dwarf shrimp are still fair game for most species.
Territory: Not strongly territorial, but still needs room so its working space does not overlap the next fish.
Planted tanks: excellent — easy plant ideas
In the glass: typical and warning signs
- Eight or more hold midwater with the copper-neon line flashing in planted tanks.
- In-school sparkle is normal; they are not fin shredders in an honest group.
- Scattered, pale fish at the glass usually need more of their own kind first.
- Losing every feed to danios is competition before you change brands again.
- Low listed risk as aggressors; they get bullied by barbs long before they bully others.
- They rarely wreck short-finned robust neighbours in a proper school.
- Pull them from barb-dominated midwater before blaming ‘poor stock.’
- Increase school size before adding another dither species to fix hiding.
Fish behaviour can vary between individuals and tank setups. Always observe new fish closely after introduction.
Water, food, and grouping
Hardness
soft
Diet
omnivore
Glowlight tetras take fine flake and micro-pellets in the midwater scramble and hold the neon line better with tiny frozen foods a few times a week. Feed a pinch they can reach before surface specialists clear the film. Soft-to-medium settled water beats hard swings for long-term colour.
Shrimp & snails
Cherry shrimp and other dwarfs can coexist with peaceful small fish; baby shrimp are food for almost anything that finds them.
Schooling species — buy 6+ together. Smaller groups stress and lose colour.
- Hold 22 to 28 °C steadily on a real thermometer, not the dial on the heater.
- Aim for pH 5.5 to 7.5 and a hardness you can re-test in two weeks. A one-time strip in the shop car park is not a water test.
- Schooling species. Buy 6 or more from the same tank on the same day before adding any centrepiece fish.
- Tank volume meets or exceeds 60L published minimum for adults.
- You can stock at least 6 individuals (group welfare).
- Heater can hold 22–28°C without cooking cooler-water tank mates.
Explore and stocking hubs
Tank-mates hub, matching guides, category peers, and litre stocking lists around this species’ minimum tank.
Plan with tools
Check mates as pairs first, then add this fish in the tank builder for the full stocking.
Filtration & heating
A 60L minimum tank needs a filter rated for at least 240L/hr turnover and a heater to hold 22–28°C reliably.
Plant suggestions
Glowlight Tetra does well in planted tanks. Plants compatible with 22–28°C and pH 5.5–7.5:
Research: partially verified · Confidence: high · 3 linked source(s). We do not invent citations.
How Fishori evaluates compatibility (same logic as pair and tank tools).
- Seriously Fish. Hemigrammus erythrozonus
Primary: aquarium size, water chemistry, behaviour, and compatibility (URL verified in upgrade script; recheck if site content changes).
- FishBase. Hemigrammus erythrozonus
Secondary: taxonomy, distribution, and maximum length in nature; cross-check with aquarium import lines and measured tank parameters.
- Wikipedia. Hemigrammus erythrozonus
Secondary: general species context; verify all husbandry numbers against a dedicated aquarium care sheet and your test kit, not a single table row.
Evidence notes
- The Seriously Fish profile for the binomial in this record was successfully reached as the primary aquarium reference.
- FishBase contributes natural-range size and habitat context. Translate those numbers through your heater, your water report, and your tank footprint before stocking.
- Wikipedia is only cited if the article URL returned OK. Use it for orientation, not as the only care sheet for an import.
- All compatibility text reflects typical hobby experience and the Fishori model. Individual fish, shop stress, and the order tank mates are added in can still defy a single-paragraph label.
Featured compatibility checks
Curated pair pages for Glowlight Tetra. Each opens a full verdict — not just a list label.
Common questions about Glowlight Tetra
- How big do Glowlight Tetra get?
- Glowlight Tetra adults reach about 4 cm. Shop fish look smaller; stock for the adult length.
- What size tank does Glowlight Tetra need?
- 60L is the planning floor for adult swimming space and bioload. A 73L+ tank is the more comfortable long-term footprint. Length and depth matter as much as raw litres for active or territorial fish.
- Are Glowlight Tetra aggressive?
- Glowlight tetras are peaceful midwater schoolers that stay calmer and brighter in honest numbers of eight or more. They do not police the tank or shred fins. Washout and scattering usually mean under-stocking or midwater competition, not a bad strain from the shop.
- Do Glowlight Tetra need to be kept in a group?
- Schooling species — buy 6+ together. Smaller groups stress and lose colour.
- What is the most common mistake with Glowlight Tetra?
- Buying four glowlights as a ‘sample school’ is how the stripe never shows. They need eight or more to school tightly; four fish scatter and look washed out. Budget for a real school up front, or wait — token numbers are a display idea, not a glowlight plan.
- What fish can live with Glowlight Tetra?
- The Glowlight Tetra profile lists Dwarf Gourami, Ember Tetra, Harlequin Rasbora, Neon Tetra among its safer pairings (engine-checked GOOD). Angelfish, Betta, Corydoras Catfish, Discus are conditional (CAUTION): workable only with the specific conditions on each pair page. Avoid Green Terror, Jack Dempsey, Oscar (RISKY). Run the pair checker for your exact water and tank size before stocking.