Fish comparison
Harlequin Rasbora vs Neon Tetra
How the Harlequin Rasbora and Neon Tetra compare on care, size, water and temperament, and which fish suits your tank.
By Mike ElmiraUpdated
TL;DR, Harlequin Rasbora vs Neon Tetra
The Harlequin Rasbora and the Neon Tetra come up together a lot when people are choosing a fish, and they are close enough to weigh side by side. Both are happy somewhere around 22 to 26 °C and pH 5.5 to 7, so a single tank can suit either one. The Harlequin Rasbora is the more forgiving of the two, which matters if this is an early tank, while the Neon Tetra rewards a bit more attention. Read the full care notes on each below and pick the one whose look and pace fit the tank you're building.
Group compatibility overview
Excellent fit
Every key parameter overlaps and no major conflicts surfaced.
4 notes
Temperature
- Harlequin Rasbora22–28 °C
- Neon Tetra20–26 °C
pH
- Harlequin Rasbora5.5–7.5
- Neon Tetra5.5–7
Hardness
- Harlequin Rasbora2–12 dGH
- Neon Tetra1–8 dGH
What to plan for
- Harlequin Rasbora schools, stock at least 8You've planned for 1 harlequin rasbora. Harlequin Rasbora need a group of at least 8 to feel safe and shoal naturally, below that they're stressed and lose colour. Dial up the count, or remove the species.
- Neon Tetra schools, stock at least 10You've planned for 1 neon tetra. Neon Tetra need a group of at least 10 to feel safe and shoal naturally, below that they're stressed and lose colour. Dial up the count, or remove the species.
- No bottom teamNo bottom-dwelling fish or shrimp. A small group of corydoras or a shrimp colony picks up leftover food and keeps detritus in check.
- 100% of your fish swim in the midHeavy concentration in a single zone. Spreading stocking across all three levels makes the tank read fuller for the same bioload.
Full attributes
Every parameter, side by side| Parameter |  FishHarlequin RasboraTrigonostigma heteromorpha |  FishNeon TetraParacheirodon innesi |
|---|---|---|
| Category | Fish | Fish |
| Origin | Thailand, Malaysia, Sumatra | Upper Amazon basin, South America |
| Family | Cyprinidae | Characidae |
| Temperature | 22–28 °C | 20–26 °C |
| pH | 5.5–7.5 | 5.5–7.0 |
| Hardness (dGH) | 2–12 | 1–8 |
| Flow rate | Low to Medium | Low to Medium |
| Min tank | 60 L | 60 L |
| Adult size | 4–5 cm | 3.5–4 cm |
| Difficulty | 1 / 5 | 2 / 5 |
| Lifespan | 5–8 yrs | 5–8 yrs |
| Diet | Omnivore | Omnivore |
| Water column | Mid | Mid |
| Schooling | Yes | Yes |
| Plant safe | Yes | Yes |
| Shrimp safe | Mostly (may eat shrimplets) | Yes (with adults; may eat shrimplets) |
Frequently asked questions
Direct answers to the questions search engines and AI assistants surface most often about this species.
Can you keep Harlequin Rasbora and Neon Tetra together?
Yes. Their temperature and pH ranges overlap around 22 to 26 °C and pH 5.5 to 7, so one set of water conditions keeps both comfortable. Match group sizes and cover the usual planted-tank basics and they share a tank fine.
Which is easier to keep, the Harlequin Rasbora or the Neon Tetra?
The Harlequin Rasbora is the easier of the two, closer to very easy, while the Neon Tetra leans beginner-friendly.
Do Harlequin Rasbora and Neon Tetra need the same water?
Close to it. Aim for 22 to 26 °C and pH 5.5 to 7 and you're in the shared sweet spot for both. Full ranges are in the table above.
What's the main difference between the Harlequin Rasbora and the Neon Tetra?
It comes down to look, size and pace rather than one being flatly better. The table above lays the numbers out row by row.