Fish comparison
Clown Killifish vs Marbled Hatchetfish
How the Clown Killifish and Marbled Hatchetfish compare on care, size, water and temperament, and which fish suits your tank.
By Mike ElmiraUpdated
TL;DR, Clown Killifish vs Marbled Hatchetfish
The Clown Killifish and the Marbled Hatchetfish 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 24 to 26 °C and pH 5 to 6.5, so a single tank can suit either one. Neither is harder than the other to keep, so the choice comes down to look and stocking rather than skill. If tank space is tight, the Clown Killifish needs less room to feel settled; give the Marbled Hatchetfish the nod when you have the litres to spare.
Group compatibility overview
Good fit
Workable as-is, only minor advisories to plan around.
1 warning · 1 note
Temperature
- Clown Killifish22–26 °C
- Marbled Hatchetfish24–28 °C
pH
- Clown Killifish4.5–6.5
- Marbled Hatchetfish5–6.5
Hardness
- Clown Killifish1–6 dGH
- Marbled Hatchetfish1–8 dGH
What to plan for
- Marbled Hatchetfish schools, stock at least 6You've planned for 1 marbled hatchetfish. Marbled Hatchetfish need a group of at least 6 to feel safe and shoal naturally, below that they're stressed and lose colour. Dial up the count, or remove the species.
- All fish are surface-dwellersThe bottom of the tank is unstocked, debris will build up. Add a bottom team (corydoras, otocinclus, hillstream loach) or shrimp.
Full attributes
Every parameter, side by side| Parameter |  FishClown KillifishEpiplatys annulatus |  FishMarbled HatchetfishCarnegiella strigata |
|---|---|---|
| Category | Fish | Fish |
| Origin | Coastal Sierra Leone, Guinea, Liberia | Amazon basin, Peru & Brazil |
| Family | Nothobranchiidae | Gasteropelecidae |
| Temperature | 22–26 °C | 24–28 °C |
| pH | 4.5–6.5 | 5.0–6.5 |
| Hardness (dGH) | 1–6 | 1–8 |
| Flow rate | Still | Still to Low |
| Min tank | 30 L | 75 L |
| Adult size | 3–3.5 cm | 3.5–4.5 cm |
| Difficulty | 3 / 5 | 3 / 5 |
| Lifespan | 3–4 yrs | 3–5 yrs |
| Diet | Micropredator | Micropredator (insectivore) |
| Water column | Top | Top (strictly surface) |
| Schooling | Loose group | Yes |
| Plant safe | Yes | Yes |
| Shrimp safe | Yes (adults only, will hunt shrimplets) | Yes |
Frequently asked questions
Direct answers to the questions search engines and AI assistants surface most often about this species.
Can you keep Clown Killifish and Marbled Hatchetfish together?
Yes. Their temperature and pH ranges overlap around 24 to 26 °C and pH 5 to 6.5, 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 Clown Killifish or the Marbled Hatchetfish?
They sit at the same care level, both middle-of-the-road, so neither is the obvious beginner pick. The decision is really about the look you're after.
Do Clown Killifish and Marbled Hatchetfish need the same water?
Close to it. Aim for 24 to 26 °C and pH 5 to 6.5 and you're in the shared sweet spot for both. Full ranges are in the table above.
What's the main difference between the Clown Killifish and the Marbled Hatchetfish?
Space. The Clown Killifish wants about 30 litres minimum and the Marbled Hatchetfish around 75, so tank size can settle it.