In this care guide, we answer some of the most frequently asked questions about this lovable bottom dweller.
What are Corydoras?
They belong to the subfamily Corydoradinae, which is part of a larger family Callichthyidae. Let’s take a look at its place as a genus within the scientific classification:
- Kingdom: Animalia
- Edge: Chordata
- Class: Actinopterygii
- Order: Siluriformes
- Family: Callichthyidae
- Subfamily: Corydoradinae
- Genus: Corydoras
They are named for the bony plates on their body armor. To ward off predators, these little catfish also have sharp spines on their fins that can sometimes produce a slight venom when stressed. In other words, don’t try to catch them with your bare hands!
Depending on the species, most Corydoras are tropical freshwater fish that enjoy temperatures between 22 and 27°C. For example, Corydoras Paleatus and Corydoras Julii are at the cooler end of the spectrum, while Corydoras sterbai can live at higher temperatures. They also prefer pH levels ranging from 6.5 to 7.8.
They inhabit the bottom of the aquarium as they are bottom-feeding scavengers. Coridoras are community fish and are not aggressive or territorial at all.
In the wild, Corydoras have been observed in large groups ranging from 20 to hundreds of the same species. They are most active during the day and their maximum activity occurs at dawn and dusk.
What Size Tank Do Leathery Catfish Need?
For dwarf species, a 10-gallon tank may be adequate, but I recommend 20-gallons or more for most other varieties. As they are relatively small fish they prefer the safety of the school, so I suggest a group of six Corydoras or more (all of the same species).
These peaceful bottom dwellers can cohabit with almost any fish in the community that will not eat or attack them. For example, don’t keep Corydoras with goldfish -pez-dorado/” class=”rank-math-link”> goldfish, which get quite large and suck up anything that fits in their mouths.
If you’re looking for fish breeding ideas, a 20-gallon aquarium could hold a school of Corydoras swimming in the bottom, a school of small Tetras swimming in the middle layer, and a center fish like a Honey Gourami. Add some lush aquarium plants and you have a miniature ecosystem in your living room.
Types of Corydoras
There are many different types of corydoras. Some estimates point to more than 160 species worldwide. Additionally, many more variations exist (several hundred is a rough estimate) and are maintained by aquarists. However, the vast majority of species are not scientifically classified.
Here are some of the most prominent types of corydoras:
Bronze cory (Corydoras aeneus)
The bronze cory is probably the most popular and most preserved of all the cory types. It is basically a single color (bronze) variation of the species known as the green cory.
They are small, lively, and peaceful, whose native habitat is the slow-moving, muddy waters of South America. In an aquarium environment, they reach a maximum of 7 cm.
The preferable water temperature for this type of Cory is between 22-26⁰C and slightly acidic with a pH ranging from 5.8 to 7.0.
Panda Cory (Corydoras panda)
The Panda cory is another popular species of the Corydoras genus. They are native to parts of the Amazon in Peru and are also found in Ecuador.
Its name comes from the black markings around its eyes and the black spots located on the back. Being one of the smallest corydoras, they only grow 5 cm long in an aquarium environment.
They are very social and often form closed schools with species of their own kind, but also with other bottom-dwelling species.
Their ideal water temperature is 20-25⁰ C. The water pH in which they feel most comfortable is between 6.0 and 7.0.
Cory pepper (Corydoras paleatus)
The pepper cory was one of the first species raised in tanks. Nearly all fish sold around the world today are hatchery-raised.
Being peaceful scavengers, they constantly swim around the bottom of the aquarium in search of food. They get along with almost all other species of fish, making them perfect for community aquariums.
Its growth depends on the sex of the fish; the male can grow up to 6cm, while the females are slightly longer, 7.5cm at most.
The preferred temperature for this species is between 22-25 ⁰C. The pH of the water should be slightly acidic with pH values between 6.0 and 7.0.
Cory Julii (Corydoras julii)
This Cory species is native to the lower Amazon region, primarily in the rivers of Brazil.
They are often confused with their other relatives from the upper Amazon areas, three-striped Cory. The main difference is that Julii spots are not directly connected to each other, while the others have more linear stripes and are connected in larger chains.
Its body is between silver and gray, while its spots are mostly black. Like all her cousins, they are peaceful bottom scavengers.
An adult Julii Cory is about 6cm long. The temperature in which they thrive is in the range of 22-26 ⁰C. They prefer a somewhat neutral pH between 6.5 and 7.8, which would be good for them.
Pygmy Cory (Corydoras pygmaeus)
This is one of the most unique species that exist, being one of the smallest of the subfamily. They only grow to about 1 inch in size in an aquarium environment.
The other unique thing about them is their depth preference. Unlike most other corydoras, they are mid-water swimmers, as they do not live at the bottom of the tank.
Instead they tend to rest on plants within the aquarium. The temperature that best suits these miniature pets is between 21-25 ⁰C. They prefer a near neutral water pH in the range of 6.5 to 7.5.
Bandit Cory (Corydoras metae)
They are one of the oldest species of corydoras kept in an aquarium, originally found in 1914. They get their name from the Meta River in Colombia, where they were first found.
They are called “bandit” because of the black spots around their eyes that resemble the mask often worn by bandits. In contrast to their name, they are a peaceful, schooling species and only grow to 5 cm long.
One thing to keep in mind when keeping them is that they are more sensitive to variations in water temperature. Their ideal temperature is in the range of 22-26 ⁰C and they prefer slightly acidic water to neutral with a pH between 6.5 and 7.0.
Do Corys need a sand substrate?
Corydoras have fine beards or whiskers to help them find food, so it’s a good idea to put sand or smooth gravel on them. In general, it helps to give them larger foods like worms and catfish food, which can stay on top of the substrate and not get caught in cracks where the Corys can’t reach them.
In the wild, Corydoras can be found in sharp substrate, so if your corys start to deteriorate, it may be caused by other factors such as poor water quality.
What should I feed my Cylindrical Catfish?
Speaking of diet, Corydoras are not picky eaters and will eat anything small or soft enough to fit in their mouths.
They love worms of all kinds, so you can try live black worms or frozen blood worms. They also enjoy specific foods like wafers or other community foods that sink.
Algae aren’t primarily part of their food, so you’ll need to feed them specifically to make sure they get enough nutrition. If they are housed with more aggressive eaters, it can be easy for the corydora to be outcompeted during feeding times, causing them to become malnourished.
Can you breed Corydoras in an aquarium?
Yes, very easily! Many aquarists find that their Corydoras reproduce all the time without any special effort. The males have a smaller and slimmer profile, while the females are rounder and larger to hold all the eggs.
You should condition them (or prepare them for breeding) by feeding them plenty of nutritious food, such as live black worms and frozen blood worms.
You can also induce spawning by introducing cooler than normal water (a few degrees) during water changes to mimic the rainy season. Pretty soon, you’ll find round sticky eggs all over the walls and decorations of the tank.
If you want to breed in the same tank they live in, provide plenty of protection such as a dense stand of java fern and remove other fish species.
All fish (including the parents themselves) will gladly eat the eggs if given the opportunity. For a higher survival rate, you can remove the eggs (with your fingers or anything else that works for you) and put them in a separate tank to raise the fry.
Feed baby Corydoras plenty of live brine shrimp and fry food, stay on top of changes in the water, and enjoy a whole new generation of Corydoras.