Julii corydoras (Corydoras julii) care guide

Group
Freshwater fish
Other names
Julii cory, Leopard cory, Leopard corydoras, Leopard catfish, Hoplisoma julii
Family
Callichthyidae (armoured catfishes)
Origin
Lower Amazon drainage and coastal rivers of north-eastern Brazil, including the Parnaíba and Piauí systems.
Water
freshwater
Maximum size
5.2 cm
Temperature
23–26°C
pH
5.5–7.5
Hardness
Soft to medium, 2–12 dGH
Minimum tank
81 litres
Care level
beginner
Temperament
peaceful

Care

The julii cory is a lively, gregarious species that should be kept in a group of at least 6, ideally more of the one kind. Seriously Fish suggests a tank with a base of about 90 × 30 cm (around 81 litres) for a group, as these are active fish that like to roam. Use fine sand, or at least smooth rounded gravel kept very clean, so the fish can sift for food without wearing down their barbels. Add driftwood, plants and some shade, leaving an open patch of floor for foraging. PlanetCatfish suggests driftwood, plants and some overhanging rock or bogwood for shade. PlanetCatfish gives 23–26 °C, slightly warmer at the low end than the 20–26 °C we used before; we now use the PlanetCatfish figure. A pH of about 5.5–7.5 and soft to medium water suit it. Keep nitrate low with regular partial water changes and do not let waste build up in the substrate, as dirty conditions quickly lead to eroded barbels and infections. Corys handle salt and many medications (especially copper) poorly, so treat with care. Darting to the surface for a gulp of air now and then is normal: they breathe air through the gut. The pectoral-fin spines are sharp and can give a painful jab, so take care when netting and handling. Most fish sold as "julii" are actually the very similar three-line cory, Hoplisoma trilineatum (formerly Corydoras trilineatus). PlanetCatfish says true julii has a spotted head and a short horizontal stripe in the middle of the flank that does not reach halfway along the body; trilineatum has worm-like, joined-up markings on the head. Without locality data they can be hard to tell apart, so do not mix the two if you hope to breed them. Females are noticeably larger and fuller-bodied than males. Name note: since the 2024 revision of the armoured catfishes it is classified as Hoplisoma julii (PlanetCatfish, FishBase, Seriously Fish and Wikipedia), but it is still sold as "Corydoras julii". PlanetCatfish gives a maximum of 5.2 cm SL. PlanetCatfish lists it as Not Evaluated; FishBase gives Least Concern on the IUCN Red List. Sources: PlanetCatfish (planetcatfish.com/common/species.php?speciesid=378); Seriously Fish (seriouslyfish.com/species/hoplisoma-julii/); FishBase (fishbase.se/summary/Corydoras-julii.html); Wikipedia (en.wikipedia.org/wiki/Hoplisomajulii). Checked October 2026.

Diet

A foraging omnivore. PlanetCatfish says it takes prepared foods that reach the bottom, such as tablets, granules and flake, and readily eats bloodworm, white worm, Daphnia and Tubifex-type worms, which also help condition it for breeding. It cannot live on scraps left by other fish.

Breeding

PlanetCatfish says spawning is rarely written up, though its members have logged several breeding reports. It breeds much like other corys. Use two or more males for each female and condition them with plenty of live and frozen food. A 50–70% water change with somewhat cooler water, along with stronger aeration and flow, imitates a rainy-season storm and often triggers spawning. Pairs adopt the "T-position", and the female then places a few sticky eggs at a time on the glass, plant leaves or spawning mops. The adults will eat the eggs, so remove either the eggs or the parents. Incubation takes around 3–4 days; once the fry have used their yolk sacs, feed microworm and newly hatched brine shrimp, keeping the water very clean.

Compatibility and tank mates

Peaceful and gregarious; PlanetCatfish calls it a peaceful, shoaling community fish. It suits most community tanks of small to medium, non-aggressive fish: tetras, rasboras, danios, peaceful barbs, livebearers, gouramis, dwarf cichlids and other peaceful catfish. Avoid large, predatory or bullying fish and persistent fin-nippers.

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

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