Aquarium fish: Sterba’s corydoras (Corydoras Sterbai)
Size: 6.5 cm
Origin: South America
Water temperature: 21-25 ° C
Aquarium volume: 54 l
Sterba’s corydoras (Corydoras Sterbai ) – a small, interestingly colored aquarium fish from the Cuirassidae family.
South America. The species is found in the Guapore River in western Brazil and northeastern Bolivia. It lives in small tributaries, streams and forest lagoons. Nowadays it is difficult to find and most of the fish on the market come from breeding farms.
Characteristics and disposition
Reaches up to 6.5 cm in length. It is characterized by an interesting spotted pattern on the body. On the head it has bright spots on a dark background, which on the body and fins turn into dark horizontal stripes on a light background. The head, abdomen, and fins may be of various golden colors. The rays of the pectoral fins are clearly golden.
The form of albino is also commercially available. Adult males are much smaller and more slender. Females are thicker and wider, especially when viewed from above. The Sterby cuirass can be confused with the very similar Corydoras haraldschultzi ( Magnificent mosaic ), which has a slightly more elongated snout and an inverse pattern on the head, i.e. dark dots on a light background.
Like other cuiras, a very calm and shoal fish. In the aquarium, it should be kept in a group of at least 6 animals. Larger amounts will be more daring and active. Kiryski belongs to the “armored” catfish group. Instead of scales, they have a specific armor, i.e.
two rows of bone plates arranged along the sides. The species name is derived from the Greek words cory (helmet) and doras (leather). Be careful when taking care of the cuirass. The first rays of their pectoral and dorsal fins are very sharp and can easily become entangled in the mesh and even prick painfully. They are adapted to survive in oxygen-poor waters.
Their modified intestine functions as an additional respiratory organ thanks to which they can draw atmospheric air from above the water. In an aquarium, you can often observe them swimming rapidly to the surface to get air. This is completely natural behavior.
Nutrition and feeding
Omnivorous and unrefined. It accepts all available dry, live and frozen foods.
Good quality dry food falling to the bottom can be given every day. Once or twice a week supplemented with live or frozen foods, e.g. daphnia, artemia, bloodworm, hydrating.
Kiryski Sterby will feel best with spacious min. 54 l aquarium designed in the style of the Amazon biotope.
River sand or substrate can be used as the substrate. For decoration, you can use dry roots, twisted twigs and leaves of e.g. oak, beech or ketapang, which will add a natural look. They should be replaced every few weeks. The roots and leaves will release tannins into the water and will color the water the color of weak tea.
Additionally, you can also put a bag with peat in the filter. The light shouldn’t be too bright. Plants in natural habitats are sparse. A peaceful species that can be a perfect complement to a social aquarium. It should not be combined with much larger and aggressive fish.
Small tetras, carps, labyrinths, cichlids and gentle catfish will be good company.
Considered one of the easier cuiras to reproduce. The spawning aquarium should have min. 45 cm long. Sand can be used as a substrate, but it is not necessary, and it is even easier to keep the fry at a sterile bottom.
You will need a small sponge filter for filtration. These fish eagerly spawn among the vegetation, so there are a few larger clumps of small-leaved plants, e.g. java moss, in the tank. The optimal parameters of water for reproduction are 6.5 pH and 24 ° C. It may help to run the water through a peat filter or use demineralized water.
When breeding cuiras, it is recommended that there are at least 2 males for each female. Spawners should be fed copiously with live or frozen food. When the females are clearly thicker – full of eggs – we perform a large (50%) change of water that is cooler by approx. 2 ° C. We repeat this process every day until spawning.
It should be noted here that many species breed seasonally. If the fish do not want to wipe in summer, try in winter. In addition, patience is recommended as some species reach sexual maturity late. Sometimes it is worth trying different approaches, e.g. replacing them at a different time of the day, increasing oxygenation, etc.
The males start their courtship by chasing the female around the entire aquarium. This behavior usually lasts for a few days until the roles reverse. Shortly thereafter, spawning takes place in the T-position typical for cuiras – the male at an angle of 90 to the female covers her head with his pectoral fins and releases the milk into her mouth. The female releases the already fertilized eggs into a basket made of her pelvic fins, then flows away and lays them on plants, a stone or the aquarium glass. The situation repeats several times and usually lasts 2-3 hours.
During the entire cycle, the adult female lays 100-200 eggs. After spawning, adult cuiras should be separated or the eggs should be transferred to a separate aquarium. Eggs mold easily. You have to closely observe and remove every rotten grain of roe. Some growers add a few drops of methyl blue to the water to prevent this from happening.
Hatching takes place after 3-4 days. Initially, the larvae feed from their yolk sac. After this time, you can start feeding them the smallest foods, e.g. brine shrimp larvae, micro nematodes.