What are Bronze Corydoras?
Bronze Corydoras or Bronze Cory Cats (Corydoras aeneus) are a species of small Catfish belonging to the genus Corydoras, which contains some 160+ species of little Catfishes.
They are considered armoured Catfish as they possess very thick and heavy scales, which weigh them down and protect them from physical injury.
They spend their lives sifting through substrate along river beds, looking for food in the form of small invertebrates like worms.
Where are Bronze Corydoras from?
Bronze Corydoras from your local fish store will likely have come from a farm where they have been bred in captivity.
In the wild however, Bronze Cories are found in a wide range of rivers and streams all across South America, from Columbia all the way down to Argentina.
Water parameters for Bronze Corydoras
Since much of South America is shrouded in the Amazon rainforest, many of the rivers that Bronze Cory Cats are found in are tannic, filled with decaying plant matter which darkens the water and lowers the pH.
For this reason, while Bronze Cory Cats are tolerable of a wide range of water parameters, they will always prefer soft acidic water over hard water with a high pH.
From our experience, these are the best parameters to keep Bronze Corydoras in healthy condition:
|6.5 – 7.6
|Low KH and GH
Another thing to note is that Catfish need to be housed in true freshwater. They often do not tolerate salt levels in the aquarium at all, so brackish tanks are not ideal for Corydoras Catfish.
Feeding and diet of Bronze Corydoras
Corydoras Catfish are mostly carnivorous – their diet consists mainly of small invertebrates and infusoria they find in the sand using their barrels.
However, they also graze on decomposing wood, which is vital for their digestion and is a necessary part of their diet.
Placing some driftwood in the tank or feeding algae wafers is highly recommended when keeping any catfish to provide them with adequate fibrous nutrition.
In captivity, Cories aren’t picky eaters. They will eat almost any food that sinks, but prefer meaty foods.
Bloodworms, tubifex and brine shrimp are all great foods as well as high protein catfish or cichlid pellets, algae wafers and spirulina biscuits for added fibre and vegetable matter.
Best tank mates for Bronze Corydoras
Cories are an amazing community fish; one of the best out there.
They are peaceful, mind their own business on the bottom of the tank and will eat up any leftover food.
Their armour and quick movements also mean that they aren’t easy targets for bullies in the aquarium either, so they can be housed with very small peaceful fish, as well as some of the larger and more boisterous species of tropical fish.
With this, if you decide to keep Cory Cats in your community tank, make sure to feed them properly and that they are being specifically fed a good diet just like your other fish.
Cory Cats cannot just survive on scraps that the other fish leave behind and all too often, Cories are seen skinny and emaciated in neglected community tanks.
So, make sure to feed plenty of protein rich sinking foods for them to thrive on.
Harlequin Rasboras go excellent with Cory Cats. They occupy a different space from them up near the top half of the tank and look amazing schooling together in open water, while the Catfish stick down below.
As mentioned, you will need to make sure enough food is getting to your Cory Cats if you decide to keep Rasboras with them.
For water parameters, Harlequins and Cories have very similar requirements, so they can be kept at their normal, comfortable slightly acidic conditions.
Black Phantom Tetra
Very similar to Harlequins, Black Phantom Tetra will occupy the upper region of the tank. They can be a little more boisterous however, and will gobble up food with much more ferocity than Harlequins, so making sure food gets to the bottom may take a little more input.
Black Phantom Tetras are found in areas of Brazil and Bolivia, so again, have very similar water requirements to Cory Cats, allowing you to keep them at their optimal water conditions.
Cherry Barbs are a great small fish for planted community tanks. They are peaceful and small, with bright red colours.
Due to their nano size, they can sometimes be targeted and bullied by larger fish; but not by Cory Cats, who spend all their time grazing along the sand, so they pair up well as tank mates.
They are also tolerable of a huge range of water parameters, and will do well in the slightly acidic or neutral pHs that Cory Cats prefer.
Since Cory Cats are bottom feeders, they do not oppose any competition towards a Betta when it comes to feeding, which is typically a large issue with Bettas in community tanks as they are poor swimmers.
Because of their different feeding habits and slow eating, neither party presents much competition towards each other, so both species can easily get the proper level of nutrition.
Bettas and Cory Cats have similar water parameters when it comes to temperature, pH and hardness.
However, Bettas need to live in relatively still water, whereas Cory Cats are a fish that lives in moving rivers with high oxygen levels.
While you cannot add a strong current to a Betta tank, you can still use sponge filters and air stones for additional oxygen, which the Cory Cats need.
Another small peaceful fish that likes to school around the upper and mid sections of the aquarium.
They are ideal as they occupy a different zone of the tank and prefer similar South American water conditions.
Be sure to feed the Cory Cats additional sinking foods like frozen bloodworms and pellets, as in large groups, Glowlights can be very fast and competitive eaters.
Kribs or Pelvicachromis are a small West African Cichlid. They are relatively peaceful as far as African Cichlids go, and so they can be housed in community tanks with ease.
Kribs can however, become territorial and aggressive if they establish a territory to breed.
For this reason, they do best in larger community tanks with fish that can hold their own and aren’t subject to being bullied. Cories are great for this as they are armoured and fast moving, so rarely make themselves vulnerable to being attacked.
Kribensis also like the same water parameters as Cory Cats; low pH, low hardness and a temperature between 23C – 28C (73f – 82f).
How to breed Bronze Corydoras
Bronze Cory Cats are fairly easy to breed when it comes to the Cory family, often being considered the easiest Cory to start with.
To condition them, keep them in a well established tank with lots of plantlife, rocks and cover.
The tank needs to have very clean water. Keep the pH low at anywhere from 6 – 7 and feed them heavily on bloodworms, tubifex, brine shrimp and other meaty foods.
After around 14 days of fattening them up on protein rich foods, the females will look large and thick with eggs.
Performing a partial water change, using cooler water, can induce them to spawn as the sudden temperature dip mimics the arrival of rains and connection of moving water in the Amazon which naturally triggers the breeding season.
How to sex corydoras
Bronze Cory Cats are sexually monomorphic (male and female look the same) although there are subtle differences in them which experienced eyes can point out.
Typically mature female Cory Cats will be larger and rounder than the males. They will have a thicker build in order to store their eggs, and will look wider from above.
As they can be difficult to sex, it is best to get a large group of at least 6 (ideally more) to ensure that you get a good mix.
Spawning and fry of Bronze Corydoras
When spawning, Cory Cats adopt the method of “egg sticking” where the female will clasp the eggs with her pelvic fins and glue them in clutches to the undersides of leaves, within mosses or even sometimes to aquarium glass.
Shortly after, and even while spawning takes place, the adult Cory Cats will eat the eggs, so it is best to remove them and place them into a different tank where they can be raised separately.
Alternatively, once the eggs have been laid in one tank, remove the adults.
The eggs typically take around 3 days to hatch and once they do, they will emerge as wigglers (the larval state of the fish) where they will be unable to swim while they absorb their yolk for the next 3 days.
Once the yolk has been absorbed, they will develop into free swimming fry and will feed on infusoria and decaying wood.
As they get older, they can be fed crushed flakes and once adult size, they will eat most fish foods that sink to the bottom of the tank.
What tank size do Bronze Corydoras need?
Bronze Cory Cats do best in intermediate to larger sized tanks. The minimum we would recommend would be a 20 gallon tank, as they need to be housed in big groups in order to truly flourish.
You can get away with housing maybe 4 Bronze Corydoras in a 10 – 15 gallon tank for a time, however, as adults, they will become stressed, as they will feel confined to a small space and are in small numbers.
What are the best plants for Bronze Corydoras?
Cory Cats do great with any aquarium plants; however, you may find that their constant burrowing into the substrate causes them to dislodge some shallow rooted plants like dwarf chain sword and young crypts.
So, here is our list for plants which are either deep rooted and strong or are rizomas and do not need to be planted into a substrate:
- Brazilian Pennywort
- Java Fern
- Jungle Val
- Java Moss
Tips and tricks for Bronze Corydoras care
Our top tip for keeping Corydoras successfully is to keep them in large groups.
- We can’t stress it enough, but they really need to be housed in schools of at least 6 or more.
All too often beginner hobbyists will keep just 2 Cory Cats or 1 Cory on their own, and end up with a depressed and stressed out fish which never comes out into the open and never does well.
Another tip is to keep just one species of Cory Cat. Again, something we see in fish stores a lot is people who want to buy 2 of each different Cory species, 2 Pandas, 2 Bronzes, 2 Salt and Pepper.
This does not work how people think it does, and while they look the same and are both Cory Cats, they are not the same species and will not gain any social benefits from living with different species.
Instead, keep 6 Pandas, or 6 Bronzes – that way, they can properly socially interact with one another and will thrive in your tank.
In the wild, these fish live in colonies numbering thousands, so being in small numbers is highly stressful for them.