The cory catfish, of the scientific genus Corydoras, comes from South American freshwater sources. Species found in home aquariums include the skunk corydoras, bronze corydoras, banded corydoras and elegant corydoras. Although there’s great diversity in this genus, the steps to getting corydoras catfish to breed are much the same for all species. Many corys “are easily bred by amateurs,” according to the authors of “Freshwater Aquariums for Dummies.” However, you will most likely need to change the conditions in your tank to induce your corys into breeding, as they don’t tend to breed without stimulation. Corys breed during the rainy season in South America.
Things You'll Need
- Frozen fish food
- Live fish food
Keep a school of one female cory and two male cory in your tank. This serves two purposes, reports corydoras expert Kristian Adolfsson of Corydoras.net. First, competition from the males will stimulate the female and males into breeding and, second, it will reduce the chance that eggs will be eaten by other females. Females tend to be more rounded and larger than the males. If you cannot sex your corys, ask an employee at your local aquarium store for help as different species have different characteristic among the sexes.
Feed the fish live and frozen foods that sink to the bottom of the tank, such as frozen brine shrimp and bloodworms. Corys feed from the bottom, so an ample supply of foods on the bottom of the tank will help stimulate them to breed.
Place small rocks or moss in the tank for the fish to lay the eggs on.
Turn the light on the tank for 10 hours a day or less. This simulates the increased darkness during the rainy season.
Lower the water temperature to the lower range of what your species needs. For example, the bandit cory catfish needs a water temperature of 70 to 79 F according to “500 Freshwater Aquarium Fish.” Lowering the water temperature closer to 70 degrees F will simulate the raining season, the normal breeding season for these South American fish. For most species, this may be all that is needed for the fish to breed.
Complete large water change if the fish have not bred. Change about 20 percent of the water in the tank with water that is at a lower temperature of about 3 to 5 degrees F than what is already in the tank as recommended by Kristian Adolfsson. This also simulates the water changes that occur in the fishes’ habitat during the rainy season.