
Source: Wikimedia Commons
Gastrodermus hastatus
One of the smallest corydoras, marked with a black diamond on the caudal peduncle. Unlike most congeners it shoals in midwater rather than staying on the bottom.
Gastrodermus hastatus occurs in the Amazon and Paraguay River basins and was moved from Corydoras hastatus in the 2024 generic revision. FishBase gives a standard length of 2.4cm and Seriously Fish 3.2cm, making it one of the smallest corydoras. A black diamond sits on the caudal peduncle, edged front and back with white. Its most distinctive trait is behavioural: it is partly adapted to feed on pelagic zooplankton and shoals in midwater instead of hugging the substrate. Aquarium conditions are 20-26C, pH 6.0-7.5 and 2-12dGH, with a 60 x 30cm base and about 54 litres as the minimum. It is extremely peaceful but too small to house with large or boisterous fish. Sinking dried food supplemented with live Daphnia and Artemia keeps it in good condition. Breeding uses two or more males per female, triggered by large cool water changes. The IUCN Red List assesses it as Least Concern.
Source: Wikipedia (CC BY-SA 4.0)
The Dwarf Corydoras grows to 2.4-3.2cm.
The ideal temperature for the Dwarf Corydoras is 20〜26℃.
Origin
South America (Amazon and Paraguay River basins)
Size
2.4-3.2cm
Temperature
20〜26℃
Sources: FishBase / Seriously Fish
Edited & verified by: BreederDirect editorial team
The taxonomic, regulatory, and husbandry data on this page are compiled and verified against the authoritative primary sources below.
Accepted name: Gastrodermus hastatus (Eigenmann & Eigenmann, 1888)
Synonyms: Corydoras hastatus
Authority databases: FishBase
Nomenclature follows global taxonomic authority databases.
Sources: CITES Appendices (species not listed) / IUCN Red List
Regulations may change. Always verify the latest information with the relevant authorities.
Find listings for this species
Sinking dried foods, Artemia, Daphnia
A 60 x 30cm base and about 54 litres is the minimum. Because it swims in midwater, open swimming space matters as much as floor area.
20-26C, pH 6.0-7.5, 2-12dGH. FishBase records pH 6.0-8.0 and 5-19dH in the wild.
Extremely peaceful and gregarious; keep at least 4-6 and ideally 10 or more. Pair it with similarly sized fish such as small characins, never with large species.
Partly adapted to pelagic zooplankton. Alongside sinking dried food, offer live Daphnia and Artemia regularly.
Two or more males per female. Repeat daily 50-70 percent water changes with soft, cooler water. Eggs hatch in 3-4 days and fry take microworm and Artemia nauplii.
Its small size makes it vulnerable to poor water quality and starvation. Fit a sponge guard over filter intakes. IUCN status is Least Concern.
Intermediate. This is an intermediate-level species. Some prior experience and knowledge of environmental management are recommended.
The ideal temperature for Dwarf Corydoras is 20〜26℃. Avoid sudden temperature changes and maintain a stable environment.
Dwarf Corydoras typically reaches 2.4-3.2cm as an adult. Size may vary depending on care conditions and individual genetics.
Dwarf Corydoras feeds on: Sinking dried foods, Artemia, Daphnia. Aim for a balanced diet with appropriate feeding frequency.
The price of Dwarf Corydoras varies significantly depending on morph, size, and lineage. Check our market price page for the latest pricing information.
Last updated: September 16, 2026