Max Size: 6.5cm

Armatus Corydoras (Corydoras armatus)

The Armatus Corydoras is a small bottom-dwelling fish that is excellent at scavenging leftover food, thus ensuring a cleaner and healthier aquarium. These Corys are attractive and peaceful species suitable for most community aquariums.

It would be best if you kept Armatus Corydoras in groups of at least six individuals as they will be much more active and confident with their kind as they are shoaling species in nature.

Ideal tankmates for the Armatus Corydoras could include small to medium Tetras, Danios, Rasboras and Livebearers, Gouramis, Dwarf Cichlids, Loaches and other peaceful Catfish. However, it would be best if you did not house them with anything aggressive or huge. If you intend to breed these Corys, you should keep them in a species only aquarium to avoid other greedy fish consuming any of their eggs.

The Armatus Corydoras will thrive in an aquarium that mimics its natural environment. To achieve this, you could use a sandy substrate and add some driftwood; standard beech is also ok to use if you thoroughly dry it and strip it of its bark. Having dim lighting will also benefit your fish.

Adding dried leaves to stain the water would complete the natural feel; however, you must replace them every few weeks so they do not rot and pollute the water. Adding some aquarium-safe peat to the filter can aid in simulating black water conditions. Although you will not find aquatic plants in this Cory's natural waters, they also enjoy a well-planted aquarium.

The Armatus Corydoras is sensitive to deteriorating water conditions; therefore, a good maintenance schedule is essential. Like all Corys, this species may lose their barbels if you keep them in poor water, so make sure you keep the substrate clean and perform regular significant water changes.

The Armatus Corydoras has a dark silvery-grey body contrasted with irregular dark spots on its flanks; these spots are more prominent as a juvenile and fade as the fish matures. In addition, these Corys have a tall pointed dorsal fin, with the first two fin rays being dark grey. All the other fins on this fish are translucent with some faint darker spotting and banding.

Quick Facts
Scientific NameCorydoras armatus
Year Described1868
Other NamesNone
Aquarium LevelBottom
DifficultyBeginner - Intermediate
Best kept asGroups 6+
Lifespan3 - 5 years
Water Parameters
Water TypeFreshwater
PH6.5 - 7.5
GH2 - 15
TDS36 - 215
73 - 79℉
22.8 - 26.1℃


Armatus Corydoras

Natural Habitat

The Armatus Corydoras is endemic to the Río Huallaga a tributary of the Río Marañón in Peru in South America. These Corys inhabit very fast-flowing blackwaters in floodplain lakes and small forest streams with a white sandy substrate. These habitats do not have much aquatic vegetation; however, they have an abundance of submerged wood, driftwood and leaflitter.


Armatus Corydoras are foraging omnivores and will readily accept good quality sinking dried foods such as pellets and algae wafers, as well as small live, frozen and freeze-dried assortments such as Tubifex, bloodworm and decapsulated brine shrimp. Providing your Corys with a varied diet will keep your fish healthy and colour-wise in tip-top condition.

Sexual Dimorphism

It can be challenging to differentiate between the male and female Armatus Corydoras. However, females usually grow a little larger than males, and sexually mature females are much more rounder and broader-bodied, especially when they are full of eggs. In contrast, the males are slimmer and shorter than females.


There are no successful breeding reports available for The Armatus Corydoras, and there is very little information on how to breed these fish. Nevertheless, these Corys are likely to produce similar to other Corys.

It would be best to set up a separate breeding tank with either a bare bottom, sand, or fine gravel substrate, and it would also help if you added an air-powered sponge filter and some clumps of java moss. For more successful results, you should have a higher ratio of males to females when breeding Corys; two males for every female is ideal. Finally, it would be better to condition the group on a mixed diet of dried, live and frozen foods as this will help to encourage spawning.

Once you can see the females are full of eggs, you should then perform a significant water change with cooler water and increase the flow and oxygenation in the tank, then repeat this daily until the fish spawn. When the fish are ready to spawn, you may notice an increase in activity; this will be the males pursuing the females.

When the females are prepared to spawn, they will allow the male to touch her with their barbels, where they will then take up the classic T-position. The female will then form a basket with her pelvic fins where she will place 1 to 4 eggs.

Once the eggs are fertilised, she will swim away and find a suitable place to deposit the eggs, usually on the tank's glass near the water with a fast current. This cycle is then repeated until she has no more eggs.

Once spawning is complete, you should remove either the adults or the eggs; otherwise, the parents will consume them. If you decide to move the eggs, you will find they are pretty strong and can be easily rolled up the glass with a finger. The new tank should be oxygenated and have the same water parameters as the breeding tank.

It would be better to add a few drops of methylene blue to the water to prevent the eggs from getting fungus; however, some eggs may still have fungus, so you must remove them straight away to prevent it from spreading.

The eggs will usually hatch between 3 and 5 days later, and the fry will initially feed on their yolk sacs. Once they have finished their yolk sacs, you will need to provide them with microworms and baby brine shrimp.

The babies appear to be less susceptible to disease if you keep them in a tank with a thin layer of sand rather than a bare bottom. Then, once the fry grows a little larger and other fish won't see them as a snack, you can introduce them to a community aquarium.

Other Corydoras of interest

Adolfos Catfish(Corydoras adolfoi)
Agassizs Corydoras(Corydoras agassizii)
Albino Corydoras(Corydoras aeneus)
Axelrods Corydoras(Corydoras axelrodi)
Banded Corydoras(Scleromystax barbatus)
Bandit Corydoras(Corydoras melini)
View all Corydoras
Date Added: 29/07/2022 10:53:58 - Updated: 29/07/2022 13:04:10