Corydoras robineae was first described by Burgess in 1983. The name Corydoras can be broken into two parts. Cory means “helmet”. Doras means “skin”. This is a reference to the double row of bony plates running across the flank of this genus. These bony plates work as a kind of armor.
The name robineae is a reference to Mrs. Ribine Schwartz. Synonym: Corydoras robinae.
The caudal fin is the most prominent feature of Corydoras robineae. On the flank just behind the dorsal fin, the spots change to five or six horizontal stripes that extend across the caudal fin. The stripes on the flank are gray/brown. Due to the lack of the gray/brown ground color on the caudal fin, the stripes become more black and white. The dorsal fin faintly shows some black stripes but is otherwise transparent. The other fins hardly show black.
The difference between males and females can be seen in this species once they reach adulthood. The females can reach a total length of about 8.5 centimeters. The males remain slightly smaller at 7.5 centimeters. The females also have a somewhat plumper body, which is certainly visible from above. Incidentally, this is a distinctive feature of all Corydoras species.
Like all Corydoras, Corydoras robineae is most comfortable in a school. They then show their active behavior more and come to the front more often. Keep them with at least 6 copies, but preferably with (much) more. In too small a group they can become very shy and skittish. The stress can considerably shorten their life expectancy in that case.
The type of location of this species is the Rio Aiuana. This is a tributary of the Rio Negro. The distribution area of Corydoras robineae is around the headwaters and the central part of the Rio Negro and its tributaries.
With their barbels, Corydoras robineae look for something edible in the substrate. In the aquarium, you can feed them with food that sinks to the bottom. They eat almost everything you offer them. Live and frozen food, but also tablets and sinking granulate. In any case, feed them alternately to keep them healthy. They often prefer live food such as white and black mosquito larvae or tubifex.
For a school of at least six copies, you need an aquarium from about 60 centimeters in length. Like all Corydoras, Corydoras robineae are bottom dwellers. They scrape around on the bottom and dig through the substrate with their barbels. Preferably use (filter) sand as a substrate so that they do not damage their barbels. It also keeps the substrate very clean. Corydoras are sensitive to dirt on and in the substrate and poor water conditions. Too much pollution can cause them to lose their barbels.
Decorate the aquarium with plants, wood, or rounded rocks. In any case, provide some shelter where they can hide if necessary.
The water should have some current. A somewhat larger filter that moves the water considerably to get rid of all the dirt is no problem for the Corydoras. Allow the outflow to run along the surface so that a good exchange of gases occurs on the surface. Corydoras love oxygenated water.
Regular maintenance is required to keep the water clean. Do not overfeed, but make sure that enough food sinks to the bottom. There should not be any food left. As a rule, keep in mind that all food must be eaten within five minutes. Change about 20 to 25% of the water every week. For Corydoras this may best be done with cold water, but take into account tankmates, some more sensitive species do not like this very well.
As for tankmates, small species from the Characidae, Cyprinidae, and Anabantidae families are a good choice. Small peaceful catfish from, for example, the Loriicaridae family can usually be kept together well. A combination with small cichlids such as Apistogramma is not always successful. Corydoras do not always care about the territory of the cichlids when swimming around in a school, which can be quite stressful for the cichlids. Only use this combination with a larger aquarium with sufficient space for all species.
Breeding Aquarium and Conditioning
You can try to breed Corydoras robineae in a community aquarium, but usually not many young survive. If you want to raise more fry, you better opt for a special breeding aquarium.
A simple glass aquarium of about 50 x 30 centimeters is sufficient. You can set up the aquarium with a heater and air filter. The bottom may remain bare, but may also be covered with a thin layer of sand. Experience shows that more fry survive when sand is used compared to a bare bottom. You can place some plants for shelter, but they are not necessary for depositing the eggs.
To start the breeding aquarium you can use water from the normal aquarium and perhaps also some filter material. This makes starting the breeding aquarium a bit easier. The water may have a temperature of about 25 to 26 degrees Celsius. The pH may be neutral around pH 7.0.
Now place the parents. Keep a ratio of 2 to 3 males per female. Feed the Corydoras robineae with sufficient live or frozen food. In particular, feeding black mosquito larvae more often seems to get them in the right mood.
To stimulate spawning, change the water with colder water. The temperature may drop to about 18 degrees Celsius. Repeat this every day until they start depositing the eggs.
When Corydoras robineae is ready to spawn, they first become very active. The males will then chase the females. When the female is almost ready to spawn, the male can caress her with his barbels. When they are both in the right mood they adopt the T position. The male grabs the females barbels with his pectoral fins and releases some sperm. The female lays 1 egg and picks up the egg with her ventral fins. The egg is fertilized by the sperm and the female looks for a place to stick her egg. Usually, this is a spot against the glass where there is some current.
You can direct the outflow of a small motor filter on the glass so that they have a good place to deposit the eggs.
The eggs are about 2 millimeters in diameter and whitish in color. About 70 eggs can be laid per female. After the eggs have been laid you will have to remove the parents. They eat their own eggs.
Raising Corydoras robineae fry
The Corydoras robineae eggs hatch after 3 to 4 days. They then still feed on their egg yolk. As soon as it is used up you can start feeding. The larvae are still small and therefore need small food. Micro worms are the preferred food for the first few days. After a week you can also give them freshly hatched brine shrimp, soon followed by finely crushed flakes or dust food.
Fungus on eggs
Corydoras eggs can become moldy fairly quickly. Immediately remove moldy eggs to prevent spreading. It is recommended to add methylene blue to the water. This drug kills fungi and bacteria (also in your filter) and turns white silicones blue! In the Netherlands it is only available at pharmacies. You can still order it in Belgium. I would try first without methylene blue.
Problems with breeding Corydoras robineae?
Breeding is somewhat easier with some varieties than with others. A few points that might be important when breeding Corydoras robineae:
- Breeding usually works better with adult animals. You cannot always breed successfully with very young animals. Therefore, give the Corydoras robineae time to mature.
- In the wild, they lay their eggs in the rainy season, which is in winter. Air pressure, weather change, etc. can have an effect on breeding behavior.
- Sometimes you have to vary a bit in the breeding method; change the water in the morning or in the evening. Use more or less cold water. Give the aquarium a little more flow or more aeration.
John de Lange