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No federal permit to keepOlga cory
Corydoras simulatus
Fishes › Catfish (Siluriformes) › Callichthyidae (Corydoras and armored catfish)
Corydoras simulatus, the Olga cory, is a species of freshwater ray-finned fish belonging to the subfamily Corydoradinae, the corys, of the family Callichthyidae, the armoured catfishes.

Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 1.9 in / 4.9 cm).
- Water: Freshwater.
- Temperature: 68–77°F (range recorded for this species).
- pH: 6–8.
- Hardness: 2–25 dGH.
- Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Water: soft, acidic water, 68–77 °F, pH 6–7, 2–12 dGH.
- Behaviour: temperament peaceful; a shoaling fish best kept in a group of six or more; suited to a community tank.
- Difficulty: Easy (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “Ideally use a substrate of fine sand, although rounded gravel is an acceptable alternative provided it's kept scrupulously clean.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Corydoras and armored catfish
Applies to most species in this group. Habitat: Shallow South American streams. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Soft sand substrate, groups of six or more, and clean water.
Diet
- Sinking pellets, wafers and frozen bloodworms.
Social life
- Keep in groups.
Health watch
- Barbel erosion on dirty or rough substrate.
Understanding the animal
About this animal
About this animal
This species is found in the Upper Meta River basin in Colombia. The fish prefers clean, clear water with a current.
Quoted from the Wikipedia article “Corydoras simulatus” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater. Stays near the bottom. Prefers clean, clear water with current. |
| Water it lives in | Freshwater, 68–77 °F (20–25 °C), pH 6–8, hardness 2–25 dH. |
| Climate | Tropical climate. |
| Behavior to plan for | Breeding: brood hiders. |
What this means for care
- Keep water within its wild range, 68–77 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 93°F (up to 94°F in the hottest sampled areas) |
| Cool-season lows | about 70°F (down to 68°F in the coldest sampled areas) |
| Average temperature | 78–80°F across sampled records |
| Relative humidity | 76–77% on average (driest month about 65%) |
| Rainfall | about 2718 mm a year |
Measured at 10 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Corydoras simulatus, the Olga cory, is a species of freshwater ray-finned fish belonging to the subfamily Corydoradinae, the corys, of the family Callichthyidae, the armoured catfishes. This species is found in the Upper Meta River basin in Colombia. The fish prefers clean, clear water with a current. It will grow in length up to 1.9 in. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Biology | Facultative air-breathing; Prefers clean, clear water with current. — FishBase |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.