Fine-spotted cory (Corydoras polystictus) care guide

Group
Freshwater fish
Other names
Fine spotted corydoras, Many-spotted cory, Hoplisoma polystictum, Corydoras polystictus, Corydoras virescens (synonym)
Family
Callichthyidae (armoured catfishes)
Origin
South America: the Paraguay River basin (Paraná–Paraguay system) in Brazil, Paraguay and nearby; type locality the upper Rio Paraguay at Descalvados, Brazil.
Water
freshwater
Maximum size
3.2 cm
Temperature
20–25°C
pH
6–7.6
Hardness
Soft to moderately hard (FishBase: 2–25 dGH)
Minimum tank
54 litres
Care level
beginner
Temperament
peaceful

Care

A small, peaceful Corydoras that should be kept in a group of at least six. About 54 litres (a 60 cm tank) is enough for a group (our estimate from its small adult size). Use soft sand, or at least smooth rounded gravel: sharp or chipped gravel wears down the barbels, which then become infected. Add driftwood, plants and some shade from overhanging wood, rockwork, tall or floating plants, while leaving open sand for foraging. Keep current gentle and the water well oxygenated, and do regular partial water changes, as Corydoras are sensitive to nitrate and dirty substrate. Give some caves, wood and plants as cover with open swimming and foraging space in front. PlanetCatfish gives 20–25 °C and pH 6.0–7.6, so it tolerates slightly cooler water than many cories. FishBase gives 22–28 °C; we use the PlanetCatfish range. Identification and sexing: the body and dorsal fin are covered in many small dark spots, and the belly is pinkish. Size is given as 3.2 cm by PlanetCatfish and 3.5 cm by FishBase. Females grow larger and are noticeably broader and fuller-bodied when seen from above; mature males are slimmer and have more pointed tips to the paired fins. Name: now classified as Hoplisoma polystictum after the 2024 split of Corydoras; still sold as Corydoras polystictus. Corydoras virescens is a synonym. Status: IUCN Least Concern (assessed 2018, per FishBase). Sources: PlanetCatfish (planetcatfish.com/common/species.php?speciesid=490); FishBase (fishbase.se/summary/Corydoras-polystictus.html). Checked October 2026.

Diet

An omnivorous scavenger that sifts the sand for small invertebrates. Offer good-quality sinking pellets, tablets or granules as the staple, plus frozen or live bloodworm, Daphnia, brine shrimp and small worms several times a week. Make sure food actually reaches the bottom, as faster mid-water fish will take it first, and feed some after lights-out.

Breeding

Has been bred in aquariums, though PlanetCatfish holds only one breeding report. Spawning follows the usual Corydoras "T-position": the female collects the eggs in her pelvic fins, they are fertilised, and she places them on clean flat surfaces such as the aquarium glass. Condition a group (ideally more males than females) on live and frozen food, then trigger spawning with a large, slightly cooler water change. Remove the eggs to a separate container, treat or remove any that fungus, and raise the fry on infusoria or microworm and then baby brine shrimp, with frequent small water changes.

Compatibility and tank mates

A peaceful shoaling catfish for a calm community of similar-sized fish: small tetras, pencilfish, hatchetfish, rasboras, dwarf cichlids such as Apistogramma, and other Corydoras or small plecos. At just over 3 cm it needs small, gentle companions. Avoid large or boisterous cichlids, fin-nippers that pester bottom-dwellers, and any fish big enough to swallow it. Very small shrimp fry may be eaten, but adult shrimp and snails are left alone.

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

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