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Corydoras are small, peaceful catfish that spend their days sifting through the substrate in busy little groups. They're hardy, full of character and suit almost any community tank, as long as you give them the right floor to live on.
Corydoras at a glance
| Size | 2.5–7cm depending on species |
| Minimum tank | 60 litres (pygmy corys: 30 litres) |
| Group size | At least 6 of one species |
| Temperature | 21–26°C for most species |
| pH | 6.0–7.8 |
| Lifespan | 5–10+ years |
Best corydoras for beginners
- Bronze corydoras and albino corydoras: the hardiest choice.
- Peppered corydoras: happy in slightly cooler water.
- Panda corydoras: small and very popular.
- Leopard corydoras and green laser corydoras for something more striking.
- Pygmy corydoras for nano tanks: they swim mid-water in shoals.
Corys are social. Keep at least six of the same species, as they shoal most confidently with their own kind.
Substrate: the most important choice
Corydoras feed by pushing their sensitive barbels (whiskers) into the substrate. Sharp gravel wears these away and can lead to infection. Fine, smooth sand is ideal. Try Hugo Kamishi Natural Aquarium Sand or browse our freshwater substrates. Smooth, rounded fine gravel is acceptable.
Keep the substrate clean with regular siphoning using a gravel cleaner, as waste trapped in the sand affects corys first.
Tank setup
- Open sandy areas to forage, with plants and driftwood for shade.
- Good filtration with moderate flow. See external filters.
- Stable temperature with a reliable heater.
- A tight lid: corys occasionally dash to the surface for a gulp of air, which is normal.
Feeding
Corydoras are not just cleaners. They need their own food, which must reach the bottom. Feed sinking pellets or wafers such as Hikari Mini Algae Wafers or Hikari Sinking Carnivore Pellets, ideally after lights out when they're most active. Add frozen bloodworm and brine shrimp a few times a week.
Tankmates
Corys get on with almost all peaceful fish: tetras, rasboras, guppies, gouramis, angelfish and bristlenose plecos. Avoid large or aggressive fish and anything that will compete hard for bottom food.
Common problems
- Worn barbels: switch to sand and improve cleaning.
- Sensitivity to medication: corys, like other scaleless fish, can react badly to some treatments. Check the label and consider a reduced dose.
- Losses in new tanks: add corys to a mature, cycled tank.
