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Peaceful nano fish.
248 species in our list are a good match.
Peaceful nano fish.
Micro sinking foods.
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Females are larger and noticeably rounder and broader-bodied than males, especially when full of eggs.
Common problems. Tap one to see the signs. This is a guide, not a diagnosis.
Egg-scatterer · Moderate
Lays eggs mostly on the tank glass, often where flow is strong; spawning is triggered by a large (50-70%) cooler water change with more oxygen and flow, ideally 2 males per female.
Keep a group of 10 or more. Females are slightly larger.
A 10 gallon (40 L) tank with fine sand, plants and a sponge filter. 22-26 C.
A cool water change and good small live foods.
The female holds 2-4 eggs at a time between her pelvic fins and places them; a spawning can total about 100 eggs. Eggs hatch in about 3-5 days.
Feed infusoria, microworms and baby brine shrimp. Fry are tiny. Remove eggs or raise in the same tank with gentle filtration.
Described by Joachim Knaack in 1966; the name pygmaeus means 'dwarf'. Unlike most corys it swims in midwater shoals. Now Gastrodermus pygmaeus.
Joachim Knaack described the pygmy cory in 1966. At about 2.5 cm, it is one of the smallest corydoras. Unlike most corydoras, it often swims in small schools in mid-water, making it a lively choice for nano tanks.
First described by Joachim Knaack in 1966.
16 facts checked with sources
Moved to the genus Gastrodermus in the 2024 Corydoradinae revision (Dias et al.), not to Hoplisoma. Keep Corydoras pygmaeus as an other name. Seriously Fish says it is most often confused with G. hastatus (dark diamond spot at the tail base vs. a dark stripe along the side in G. pygmaeus); C. habrosus is also sold as a 'pygmy' cory by some shops (not checked here).
FishBase: Gastrodermus pygmaeus summary · Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Legacy has no family; recorded as sourced. Subfamily Corydoradinae.
FishBase: Gastrodermus pygmaeus summarySL (standard length). FishBase 2.1 cm SL for males/unsexed; Seriously Fish max 3.0 cm SL; Wikipedia gives typical females 2.5 cm. Legacy 2.5 sits in the range.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus) · FishBase: Gastrodermus pygmaeus summary · Wikipedia: Pygmy corydorasFishBase agrees with legacy 6-8; Seriously Fish (preferred for husbandry) gives 6.4-7.4.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus) · FishBase: Gastrodermus pygmaeus summaryLegacy has no hardness. Seriously Fish tolerates 2-15 but prefers below 8 (its quick-facts box says 0-8); recorded the preferred 2-8.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus) · FishBase: Gastrodermus pygmaeus summary45 x 30 cm base x 30 cm height = 40,500 cm³ = 40.5 L, rounded to 40 L (Seriously Fish shows ~41 L). Legacy 30 L is too small.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Legacy 8 is within 'at least 6, preferably 10+'.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Easily intimidated by larger tankmates.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Unlike most corys it swims in midwater shoals. FishBase lists it as demersal (general habitat).
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Seriously Fish difficulty rating 'Moderate' (5 of 8 measures).
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Legacy has no range; recorded as sourced. Wikipedia also lists Nanay (Peru) and Aguarico (Ecuador) tributaries, but Seriously Fish and FishBase give the Madeira basin only.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus) · FishBase: Gastrodermus pygmaeus summaryLegacy 'egg layer' and cool-water-change trigger agree; Seriously Fish notes eggs usually go on the glass.
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)Wikipedia gives about 100 eggs per spawning (citing FishBase). Legacy 10-30 is likely low; hatch time agrees.
FishBase: Gastrodermus pygmaeus summary · Wikipedia: Pygmy corydoras · Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus)IUCN Least Concern (per FishBase, assessed 2020).
Seriously Fish: Corydoras pygmaeus (now Gastrodermus pygmaeus) · FishBase: Gastrodermus pygmaeus summary · Wikipedia: Pygmy corydoras