Corydoras pygmaeus
Unlike most corys, swims mid-water in tight shoals. Soft, fine sand substrate protects barbels. Combine with chili rasboras or ember tetras for a stunning nano scape.
Pygmy Corydoras (Corydoras pygmaeus) reaches 2.5–3 cm as an adult and needs a minimum tank of 40 L. Native to Madeira River basin, Brazil, it lives in the mid (unusual for cory) water column with a peaceful temperament. Aim for 22–26 °C, pH 6.0–7.5, and 2–10 dGH hardness. Lifespan is 3–4 years with good care. Keep pygmy corydoras in groups of 8+, yes schoolers need numbers to display natural behaviour. Diet: omnivore (sinking), Sinking micro pellets, crushed flake on the substrate, baby brine shrimp, bloodworms. Plant-safe: Yes. Shrimp-safe: Yes (adult shrimp).
Care at a glance
Unlike most corys, swims mid-water in tight shoals. Soft, fine sand substrate protects barbels. Combine with chili rasboras or ember tetras for a stunning nano scape.
By Mike ElmiraUpdated 2 min read
Part of our complete guide to aquarium fish for the planted tank.
The parameters that decide whether pygmy corydoras fits in your tank.
Mid (unusual for cory)
Yes
Group of 8+
Callichthyidae
Omnivore (sinking)
Sinking micro pellets, crushed flake on the substrate, baby brine shrimp, bloodworms.
3–4 yrs
Medium
Sandy forest stream margins of the Madeira basin
Madeira River basin, Brazil
Tank-mate safety and the species this one is documented to thrive (or fail) alongside.
Tetras (all the small ones), small rasboras, otocinclus, cherry shrimp, sparkling gouramis, German blue rams.
Anything boisterous that bullies bottom fish. Loaches that compete for substrate.
Hard-won lessons from the tank.
Watch them gulp air at the surface — that's normal accessory respiration via the intestine. If they're doing it constantly, water quality is degraded; test ammonia/nitrite.
'Corydoras' = 'helmet skin' (their bony plates). 'Pygmaeus' = 'dwarf'.
What can go wrong and how to spot it.
Failure modes, in order of how dramatic the fix is.
Robust if acclimated. Watch for barbel erosion on coarse substrate.
Often called 'bottom feeders' and assumed to scavenge — they need their own food. Sinking pellets and bloodworms after lights-out. They will starve in a tank that doesn't drop food past upper-level competition.
The practical routine, read top to bottom.
40 L+. Soft fine SAND substrate (gravel damages barbels). Hiding spots — driftwood, plants, leaf litter. Moderate flow. Decent surface area for the schooling display.
2–3 weeks. Soft sand substrate even in QT.
Where it comes from, how it behaves, and the variants you'll see at retail.
Where it lived before it came home.
Madeira River basin in Brazil; quiet backwaters with sandy substrate, leaf litter, and submerged roots.
Micro-invertebrates, biofilm, decaying plant matter.
Not threatened. Most stock is captive-bred now.
How they pair, reproduce, and grow.
Females larger and rounder; males smaller, slimmer, slightly more contrasted patterning.
T-position spawners like other corys. Soft acidic water, cooler water-change trigger (drop 2–3 °C), 24–26 °C. Eggs stuck to glass or broad plant leaves. Easy to breed but the fry are tiny — infusoria/microworms required.
The named cultivars and the lookalikes worth flagging.
Wild type only. C. hastatus (dwarf corydoras) and C. habrosus (salt-and-pepper) are commonly confused/sold mixed.
Direct answers to the questions search engines and AI assistants surface most often about this species.
Pygmy Corydoras (Corydoras pygmaeus) needs a minimum tank of 40 L. They live in the mid (unusual for cory) water column and should be kept in groups of 8+, so a longer footprint matters more than depth.
Target 22–26 °C, pH 6.0–7.5, and 2–10 dGH hardness. Acclimate slowly when moving them between water sources.
Shrimp safety: Yes (adult shrimp). Plant safety: Yes.
Pygmy Corydoras are omnivore (sinking). Sinking micro pellets, crushed flake on the substrate, baby brine shrimp, bloodworms.
On Fin & Stem's 1–5 difficulty scale this species rates 2/5. Forgiving, beginner-friendly once the tank is cycled. Breeding difficulty: medium.
Typical lifespan in a well-maintained tank is 3–4 years.
A planted tank is a system. Pair this fish with one entry from each other pillar to plan the whole scape.
