Bronze Corydoras (Corydoras aeneus): Ultimate Care Guide


Bronze Corydoras are small freshwater catfish. Corydoras can come in a variety of colors and are often named after the color of their body. These fish are commonly injected with dye to enhance their color. However, It is recommended to stay away from dye-injected fish, as the dye can cause long-term health problems.

These fish are often observed darting to the surface of the water to get some air. This is very normal behavior for them and typically is accompanied by a popping noise. They do this because they have a unique ability to breathe air from the surface of the water

Are Bronze Corydoras Rare?

While several species of corydoras are considered rare, the Bronze Corydoras are not rare. They are one of the most popular fish found in stores and home aquariums. There is no way to know exactly how many Bronze Corydoras exist, but they are listed in the least concern conservation category.

Are Bronze Corydoras poisonous?

Corydoras are known to release poisonous mucus from their gills when they feel threatened. This poison will kill surrounding fish and ultimately can kill the Corydoras as well. This process is called self-poisoning.

While Bronze Corydoras are poisonous to other fish, they are not poisonous to humans. The poison they release is mildly irritating to human skin and the fish would have to be handled and stressed for a person to be affected.

Bronze Corydoras Care

These fish are great fish for the new aquarium hobbyist as they are considered fairly easy to care for. This first portion of the article is going to discuss their ideal tank environment, diet, lifespan, and more.

Are Bronze Corydoras hardy?

Bronze Corydoras are considered very hardy fish. They have been found in shallow, slow-moving rivers, and fast-flowing waters. They also have a special feature that allows them to breathe air from the surface of the water.

When a Corydora breathes from the surface of the water it can create a popping sound, but do not be alarmed by this behavior. It does not mean the water is lacking in oxygen. This unique ability allows them to be one of few fish that can survive in stagnant waters.

Bronze Corydoras (Corydoras aeneus)
Bronze Corydoras (Corydoras aeneus)

Tank Setup: Temperature, pH, and Size

Bronze Corydoras prefer their tank to be between 72 and 79 degrees F, and they thrive in waters that have a 5.8-7.0 pH. The favored tank size for these fish is 10 gallons, but a bigger tank is ideal depending on the amount of other fish present in the tank.

Corydoras prefer shallow water, so when choosing a tank it is best to place them into a long tank instead of a tall tank. They are also very shy fish and like to have many hiding places around the tank.

Corydoras have spines and barbles that are easily damaged which is why it is recommended to use smooth rocks around the tank. They also like to dig in the substrate and a rough substrate can cause damage. The best option is to use smooth-edged gravel or sand as a substrate.

Food & Diet

Bornze Corydoras are omnivores. They are bottom feeders and they eat insects, small worms, and crustaceans in their natural habitat. In aquariums, they do best when they are fed a variety of flake, pellets, and live food. They love to snack on brine shrimp, bloodworms, and daphnia.

One of the biggest problems with feeding Corydoras is that other fish often eat the food before it reaches the bottom. This can be avoided by feeding flakes and sinking food at the same time. Feeding in this manner offers a distraction and allows the sinking food to sink to the bottom.

Bronze Corydoras Lifespan & Size

In their natural habitat, Bronze Corydoras can live up to 10 years and grow to a maximum of 3 inches long. Among aquarists, they are said to only live 3-4 years in an aquarium. They can live past 5 years if they are kept in optimal conditions.

Bronze Corydoras Breeding

Bronze corydoras are relatively easy fish to breed. They will often begin breeding on their own with little to no outside involvement. The next part of this article will dive into how they breed if they lay eggs, and more.

How to Tell the Difference Between Male and Female

Male Bronze Corydoras are easy to differentiate from females as they are significantly smaller and more slender. The size difference is most notable when looking at the fish from above, but it can be observed when looking at them from a straight-on angle.

For breeding purposes, it is suggested to buy 6 or more fish at the same time. This can ensure there are males and females in the tank. Buying a couple of fish here and there increase the odds of not having any breeding pairs in the tank.

How do Bronze Corydoras breed?

In their natural environment rain often induces the breeding process among Bronze Corydoras. Their breeding starts with a period of courting which ends in the fish breeding in the typical “T” position. This position triggers the female to release eggs.

The act of breeding starts with the male chasing the female around the tank in an attempt to court her. This can take a couple of days as the males can lose track of the female they were chasing and then move on to a different female.

Many aquarists recommend having 1-2 males per female in a tank. This can speed up the process of breeding as the males will have a limited number of females to chase. These Corydoras are generally docile, but males may attack each other if they are chasing the same female.

Once the female accepts a male as her partner, she will begin to search for a suitable area to lay her eggs. After a spot has been chosen she will start cleaning it and begin to chase the male around the tank. Briefly, after that, they will get in the “T” position and start spawning.

How are Bronze Corydoras Eggs Laid?

When Corydoras are in the “T” position the eggs in the female are fertilized. She will then lay the fertilized 1-10 eggs in the area she previously cleaned. The eggs are sticky and will adhere to almost any surface. They can even lay their eggs on the glass window of a tank.

Corydoras are known to eat their eggs, so after the females have stopped laying eggs the adult fish should be isolated from the eggs. The adults can either be removed from the tank or the eggs can be removed.

Typically, the female lays 1-10 eggs at a time. After each set of eggs is laid the fish will resume the “T” position and lay another 1-10 eggs. This process continues until approximately 200-300 eggs have been laid.

The eggs may not all be laid in one area. The female may have multiple suitable places to lay her eggs. The female may also breed with more than one male in the tank. The process of laying eggs can take a couple of days.

How Long Does it Take for the Bronze Corydoras Eggs to Hatch?

Bronze Corydoras eggs take about 3 days to hatch. The eggs will start translucent and slowly turn tan or brown. If the egg stays clear then it is most likely not fertile. If a translucent egg begins to develop fuzz around it, it should be removed from the tank as it can affect the water quality.

Bronze Corydoras Disease

Bronze Corydoras are not susceptible to specific diseases. They are more prone to ich than many other diseases. However, nitrite poisoning is the most common disease among Corys. Nitrite poisoning can kill Corydoras and it should be treated as soon as symptoms start.

Symptoms of nitrite poisoning include sluggish swimming and swimming closer to the top of the tank. The top suggested solution is to perform a 30 % water change. Aquarists also recommend reducing feedings to decrease the amount of nitrite going into the water.

Bronze Corydoras Tank Mates

Bronze Corydoras are docile schooling fish. They get along with many different community fish. Aggressive fish can harm the barbles and spines of Corydoras, which is why it is recommended to keep them with other peaceful community fish.

How many Bronze Corydoras should be kept together?

Since Bronze Corydoras are schooling fish, it is best practice to keep at least 6 in a tank. These fish may seem shy at first, but they get along great when they are in a school. This community offers them a sense of safety as they are small fish that can easily be picked on.

Examples of Compatible and Incompatible Tank Mates

Other types of Corys, tetras, and swordtails are excellent tank mates for Bronze Corydoras. Aggressive fish such as Cichlids, Jack Dempseys, and Oscars are not good tank mates for these fish. Corydoras are docile and small fish that can be easily harmed by larger, more aggressive fish.

In Conclusion

Bronze Corydoras are an excellent fish for newcomers to the aquarium hobby. They are generally easy fish to care for and will breed on their own, and they get along great with other friendly community fish. Just remember to buy more than one Bronze Corydoras as they thrive better in a community.

Fish Laboratory

With decades of collective fishkeeping experience, we are happy to share the fish care tips that we've picked up along the way. Our goal at Fish Laboratory is to keep publishing accurate content to help fishkeepers keep their fish and aquarium healthy.

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