Can a betta live with pygmy corydoras?
Edited by Marin Hale · last reviewed October 29, 2026
Yes.
Both are comfortable at 75–79°F.
Plan on a tank of at least 10 gallons for both.
By tank size
| 5 gal | 10 gal | 20 gal | 29 gal | 40 gal | 55 gal | 75 gal |
|---|---|---|---|---|---|---|
| No | Yes | Yes | Yes | Yes | Yes | Yes |
Below 10 gallons there isn’t enough room for both, so the answer is no.
How to try it
Use at least a 10-gallon tank that is fully cycled and well established, since both species need a mature tank. Keep one betta with a group of at least 8 pygmy corydoras. Add plenty of floating plants and tall plants near the surface for the betta to rest under. Leave open fine sand or smooth gravel at mid-level and the bottom for the corydoras to shoal over.
- Confirm the tank is fully cycled and the water sits at 75–79°F, pH 6.2–7.4 and 2–12 dGH before buying anything.
- Plant the tank first with floating plants, tall stems and a few caves or driftwood pieces, so sight lines are broken up.
- Add the group of at least 8 pygmy corydoras first and let them settle in and start shoaling at mid-level and the bottom.
- Rearrange some decor, then add the betta so it does not treat the tank as already claimed territory.
- Feed the betta at the surface first, then drop sinking food for the corydoras so both eat without competing.
- Watch the first several feeding sessions closely before you leave them unattended.
Warning signs in the first weeks
- The betta flares, chases or repeatedly darts at the pygmy corydoras, especially when they rise to the mid-level.
- The corydoras hide constantly, stop shoaling, or stay stuck to the glass or the surface instead of foraging on the bottom.
- Torn or clamped betta fins, or nipped corydoras, which means the betta is getting stressed or aggressive.
- Corydoras missing out on food, or looking thin, because the betta guards the feeding area.
Backup plan: If the betta keeps harassing the corydoras, add more plants and visual barriers, then re-check that the water is within 75–79°F and pH 6.2–7.4. If the aggression continues, separate the betta into its own tank of at least 5 gallons, and keep the pygmy corydoras together as a group of at least 8 in the 10-gallon.
How we reached this verdict
| Pass | Water temperature | Both are comfortable at 75–79°F. |
|---|---|---|
| Pass | pH | Both are comfortable at pH 6.2–7.4. |
| Pass | Water hardness | Both handle water hardness of 2–12 dGH. |
| Pass | Size and appetite | Neither is small enough to be eaten by the other. |
| Pass | Fins | No fin-nipping risk. |
| Pass | Temperament | Temperaments are compatible. |
Side by side
| Trait | Betta fish | Pygmy corydoras |
|---|---|---|
| Tolerates | 75–82°F (24–28°C) | 72–79°F (22–26°C) |
| pH | 6–7.5 | 6.2–7.4 |
| Adult size | 2.5–2.8 in | 1 in |
| Temperament | Semi-aggressive | Peaceful |
| Smallest tank | 5 gallons (19 L) | 10 gallons (38 L) |
| Keep at least | 1 (fine alone) | 8 together |
| Swims | Top | Middle, bottom |
More betta pairings
Verdicts come from cross-checked species data and our compatibility rules. How verdicts work · Pygmy corydoras care