False adolfoi cory (Hoplisoma duplicareum) care guide

Group
Freshwater fish
Other names
Broad stripe cory, False adolfoi, Corydoras duplicareus
Family
Callichthyidae (armoured catfishes)
Origin
A small part of the upper Rio Negro system in Brazil, in clean blackwater tributaries and flooded forest with sandy, fairly fast-flowing water.
Water
freshwater
Maximum size
4 cm
Temperature
20–24°C
pH
6.4–7.4
Hardness
Soft
Minimum tank
54 litres
Care level
intermediate
Temperament
peaceful

Care

Like all corys this is a sociable fish that feels safest in company. Keep a group of six or more of the one species and you will see much more natural behaviour. It is the species formerly known as Corydoras duplicareus, moved to Hoplisoma when Corydoras was split up in 2024; PlanetCatfish lists it as Hoplisoma duplicareum, and it is still widely sold under the old name. As a fish of around 4 cm kept in a group, a tank with a base of about 60 × 30 cm (roughly 54 litres) is a sensible starting point (our estimate). Use fine sand or fine, smooth gravel so the fish can sift for food without wearing down their barbels. PlanetCatfish suggests open areas of substrate surrounded by plants, rocks or bogwood; a scattering of dried leaf litter also encourages the tiny organisms the fish like to graze on. It comes from soft, tea-coloured blackwater in the upper Rio Negro. PlanetCatfish gives aquarium conditions of 20–24 °C and pH 6.4–7.4 in soft water; these are used here in place of the wider ranges in our earlier research (Seriously Fish quotes 20–26 °C and pH 4–7). Keep the water clean with regular partial changes and do not let nitrate or waste build up in the substrate, as dirty conditions lead to barbel damage and infection. Corys are sensitive to salt and many medications, so take care when treating a tank they share. This fish is almost a twin of Hoplisoma (formerly Corydoras) adolfoi. It tends to be stockier, with a broader black band along the back and a stronger orange patch on the nape, but the reliable difference is the serrations on the rear edge of the pectoral-fin spine, which are almost impossible to see without magnification. It belongs to a group of Rio Negro corys with a similar dark back bar, including C. burgessi, C. imitator and C. serratus, so mislabelling does happen. Females are larger and fuller when viewed from above. PlanetCatfish gives a maximum of 4 cm standard length, smaller than the 5 cm in our earlier research. Like other corys it gulps air from the surface now and then, and its fin spines can give a painful jab if handled carelessly. FishBase lists it as Data Deficient on the IUCN Red List (assessed 2020); PlanetCatfish shows it as Not Evaluated. It is widely kept and has been bred by many hobbyists, so captive-bred fish are available alongside wild imports – ask the seller which you are getting. Sources: PlanetCatfish (planetcatfish.com/common/species.php?speciesid=379); Seriously Fish (seriouslyfish.com/species/corydoras-duplicareus/); FishBase (fishbase.se/summary/Corydoras-duplicareus.html). Checked October 2026.

Diet

An omnivorous forager. Feed good sinking wafers, pellets or tablets every day, and add live or frozen foods such as bloodworm, brine shrimp and blackworms. Make sure food actually reaches the bottom – it should never have to live on leftovers from the fish above.

Breeding

Bred fairly regularly – PlanetCatfish lists around 20 breeding reports. One reported spawning took place at 23 °C and pH 7.0 and produced 30–40 eggs, which hatched in about five days; Seriously Fish notes eggs may be laid on the substrate or near the waterline. Condition a group, with more males than females, on plenty of live and frozen food, then trigger spawning with a large, slightly cooler water change. Remove the eggs or the adults afterwards and feed the fry on newly hatched brine shrimp once they are free-swimming. Females are larger and rounder than males.

Compatibility and tank mates

Peaceful and gregarious, and a good choice for a soft-water community. PlanetCatfish describes typical cory behaviour and good compatibility with midwater fish such as tetras; in the wild it lives alongside small tetras, pencilfish and dwarf cichlids. Avoid large or boisterous fish and anything that might nip at or compete aggressively for food on the bottom.

Last updated 5 October 2026. Community-edited care guide on Aquatic-Auctions.

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