Fish comparison
Celestial Pearl Danio vs Siamese Algae Eater
How the Celestial Pearl Danio and Siamese Algae Eater compare on care, size, water and temperament, and which fish suits your tank.
By Mike ElmiraUpdated
TL;DR, Celestial Pearl Danio vs Siamese Algae Eater
The Celestial Pearl Danio and the Siamese Algae Eater 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 24 °C and pH 6.5 to 7.5, 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 Celestial Pearl Danio needs less room to feel settled; give the Siamese Algae Eater 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 · 2 notes
Temperature
- Celestial Pearl Danio20–24 °C
- Siamese Algae Eater24–28 °C
pH
- Celestial Pearl Danio6.5–7.5
- Siamese Algae Eater6.5–7.5
Hardness
- Celestial Pearl Danio2–10 dGH
- Siamese Algae Eater5–15 dGH
What to plan for
- Tight temperature windowThe overlap is only 24–24 °C. Heater stability matters more than usual; consider an external controller.
- Celestial Pearl Danio schools, stock at least 6You've planned for 1 celestial pearl danio. Celestial Pearl Danio 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.
- 67% of your fish swim in the bottomHeavy 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 |  FishCelestial Pearl DanioDanio margaritatus |  FishSiamese Algae EaterCrossocheilus langei |
|---|---|---|
| Category | Fish | Fish |
| Origin | Hopong area, Myanmar | Mainland Southeast Asia (Thailand, Malaysia, Indonesia) |
| Family | Cyprinidae | Cyprinidae |
| Temperature | 20–24 °C | 24–28 °C |
| pH | 6.5–7.5 | 6.5–7.5 |
| Hardness (dGH) | 2–10 | 5–15 |
| Flow rate | Low | Medium to High |
| Min tank | 40 L | 150 L |
| Adult size | 2–2.5 cm | 12–15 cm |
| Difficulty | 2 / 5 | 2 / 5 |
| Lifespan | 3–5 yrs | 8–10 yrs |
| Diet | Micropredator | Omnivore (heavy algae grazer) |
| Water column | Mid to Bottom | Bottom (grazes everywhere) |
| Schooling | Yes (loose shoal) | Loose group |
| Plant safe | Yes | Yes |
| Shrimp safe | Yes (adult shrimp) | Yes (adults safe with adult shrimp) |
Frequently asked questions
Direct answers to the questions search engines and AI assistants surface most often about this species.
Can you keep Celestial Pearl Danio and Siamese Algae Eater together?
Yes. Their temperature and pH ranges overlap around 24 to 24 °C and pH 6.5 to 7.5, 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 Celestial Pearl Danio or the Siamese Algae Eater?
They sit at the same care level, both beginner-friendly, so neither is the obvious beginner pick. The decision is really about the look you're after.
Do Celestial Pearl Danio and Siamese Algae Eater need the same water?
Close to it. Aim for 24 to 24 °C and pH 6.5 to 7.5 and you're in the shared sweet spot for both. Full ranges are in the table above.
What's the main difference between the Celestial Pearl Danio and the Siamese Algae Eater?
Temperament is the big one. The Celestial Pearl Danio is peaceful and the Siamese Algae Eater is territorial when breeding, which changes who you can house them with.