How Big Do Corydoras Get?
Short answer: Most corydoras reach 5-7 cm (2-3 inches) body length. The pygmy cory tops out at 2.1 cm; the bronze cory reaches 7.5 cm. Here is every common species sized, cited to FishBase, with the tank sizes real keepers use.
Corydoras catfish at a glance
- Scientific name
- Corydoras sp.
- Adult size
- ~2.5″
- Temperature
- 72–80°F
- pH
- 6–7.5
- Minimum tank
- 20 gal
- Temperament
- peaceful
- Social
- schooling — keep 6+
- Reference
- Wikipedia
Most corydoras reach 5-7 cm (2-3 inches) body length as adults. The smallest hobby species, the pygmy cory, tops out at just 2.1 cm.3 The largest common species, the bronze cory, reaches 7.5 cm.1 Size depends on the species: a 3.5x spread from smallest to largest. See the full corydoras care guide for water, diet, and tankmates.
Corydoras size at a glance
Body sizes are FishBase standard length (SL = body excluding tail fin). Tank-size medians from 493 real corydoras setups in our dataset.
| Attribute | Authority (FishBase) | Real tanks (AquaGauge) |
|---|---|---|
| Smallest (pygmy) | 2.1 cm SL3 | kept in median 10 gal |
| Largest common (bronze) | 7.5 cm SL1 | kept in median 20 gal |
| Median tank size (all corys) | 20 gal (493 tanks) | |
| Keepers using 10 gal or more | 87% |
Corydoras size by species
The flat “2-3 inches” you see online hides a real spread. The table below lists every common hobby species with its FishBase maximum standard length (SL, body excluding the tail fin) and IUCN conservation status.
| Species | Scientific name | Max SL | IUCN |
|---|---|---|---|
| Pygmy | Corydoras pygmaeus | 2.1 cm3 | LC3 |
| Panda | C. panda | 3.8 cm4 | NT4 |
| Julii | C. julii | 5.2 cm5 | LC5 |
| Peppered | C. paleatus | 6.6 cm (male), 7.1 cm (female)6 | LC6 |
| Sterbai | C. sterbai | 6.8 cm7 | LC7 |
| Bronze (= Albino) | C. aeneus | 7.5 cm1 | LC1 |
The albino cory is the same species as the bronze (C. aeneus), bred for colour, so its adult size is identical. Seriously Fish reports the bronze at 65-75 mm SL, consistent with the FishBase maximum.2
Note on “SL”: FishBase measures standard length, from snout to the base of the tail fin, not including the tail itself. Add roughly 15-20% for total length (tip-to-tip). A 7.5 cm SL bronze cory is about 9 cm or 3.5 inches nose to tail.
Dwarf vs standard: which fits your tank
Corydoras split into two practical size classes.
Dwarf (under 3 cm SL). The pygmy cory at 2.1 cm is the only true nano species in the common lineup. It suits a 10-gallon tank and, unlike the others, shoals in mid-water rather than on the bottom. The panda cory (3.8 cm) is small but still a bottom-dweller that does better with a 20-gallon footprint.
Standard (5-7.5 cm SL). The bronze, peppered, sterbai, and julii all fall here. They need floor space to forage, and a 20-gallon or larger is the practical minimum for a group of six.8 See how many corydoras in a tank for the full stocking breakdown.
How fast do corydoras grow
Most corydoras reach adult size within 6-12 months. Pygmy corys finish growing faster, around 4-6 months, because they stay so small. The common species (bronze, peppered, sterbai) grow steadily for about a year and may fill out in girth over the following months.
Growth rate depends on feeding, water quality, and temperature. Regular water changes, a varied sinking diet, and a group of six or more all support steady growth. See what do corydoras eat and corydoras water parameters.
What tank sizes real keepers actually use
Across 493 corydoras tanks in our dataset, the median tank size is 20 gallons (Q1 10, Q3 29). 87% of keepers house corydoras in 10 gallons or more.
| Tank size | Share of keepers |
|---|---|
| Under 5 gal | 3% |
| 5 gal | 8% |
| 10 gal | 23% |
| Over 10 gal | 65% |
The 10-gallon group is almost entirely pygmy and dwarf corys; the standard species cluster at 20 gallons and up. Plan your setup in the stocking calculator.
Lifespan and breeding
Size and lifespan correlate: the larger common species live 10-15 years with good care (sometimes 20), while the pygmy cory lives about 3-4 years. See the full corydoras lifespan by species breakdown.
Breeding follows one genus pattern: a large, cooler water change triggers spawning, the female sticks eggs to the glass and fine-leaved plants, and they hatch in about 3-4 days.2 Fry take microworm and baby brine shrimp over a thin layer of sand.
How we counted
Tank-size data comes from 493 self-reported corydoras setups scraped from fishkeeping subreddits (primarily r/corydoras). Each post was parsed for species, tank volume, and stocking count. Body sizes are cited to FishBase (the global ichthyological database) and cross-referenced against Seriously Fish and ScotCat. Full method at /methodology/.
Check your exact stocking
Add your fish below to see stocking %, filtration load and compatibility for your setup — live.
Planning a Corydoras catfish tank. We start with your corydoras catfish and filter the list to compatible tankmates — untick to see every species (incompatible ones get flagged).
Stocking — under 85% comfortable · 85–100% full · over 100% overstocked
Show the math
Gear for this setup
As an Amazon Associate AquaGauge earns from qualifying purchases. Some links below are affiliate links, at no extra cost to you. Current price and availability are shown on Amazon. Disclosure.
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Tetra 20-Gallon Aquarium Kit The right starting point for a group of standard corydoras. Includes LED lighting and filtration; the 20-gallon footprint matches the median tank size real keepers use. Check price on Amazon → -
Aqua Natural Sugar White Sand (10 lb) Soft, barbel-safe sand that lets corys forage naturally without grinding down their barbels on sharp gravel. Check price on Amazon → -
Hikari Sinking Wafers (3.88 oz) A nutritionally complete sinking staple that reaches the bottom where corys feed, rather than relying on leftover flake. Check price on Amazon → -
API Freshwater Master Test Kit Tracks ammonia, nitrite, nitrate and pH. Stable water matters more for long-term health than any single piece of equipment. Check price on Amazon →
FAQ
- How big do cory catfish get?
- Most common species reach 5-7 cm (2-3 inches) body length. The pygmy cory stays at about 2 cm / 1 inch; the bronze cory reaches 7.5 cm / 3 inches. The exact adult size depends on the species.
- What is the biggest common corydoras?
- The bronze cory (Corydoras aeneus) at 7.5 cm standard length is the largest species you will find in most shops. The albino cory is the same species, so it reaches the same size.
- How fast do corydoras grow to full size?
- Most reach adult size in 6-12 months. Pygmy corys finish faster (around 4-6 months) because they stay so small. Good water quality, a varied sinking diet, and a group of six or more all support steady growth.
- Do corydoras need a big tank?
- Standard species (bronze, peppered, sterbai) need at least a 20-gallon for a group of six. Pygmy corydoras work in a 10-gallon. Across 493 real tanks in our dataset, the median is 20 gallons.
Sources
- Corydoras aeneus (Bronze Corydoras), FishBase. View source ↗
- Corydoras aeneus, Seriously Fish. View source ↗
- Gastrodermus pygmaeus (Pygmy Corydoras), FishBase. View source ↗
- Hoplisoma panda (Panda Corydoras), FishBase. View source ↗
- Hoplisoma julii (Leopard Corydoras), FishBase. View source ↗
- Hoplisoma paleatum (Peppered Corydoras), FishBase. View source ↗
- Hoplisoma sterbai (Sterba's Corydoras), FishBase. View source ↗
- ScotCat catfish factsheets, ScotCat (electronic publication) (2025). View source ↗
Freshwater aquarist of 8+ years.
Catfish expert -- founder of ScotCat; Corydoras & pleco authority