Pygmy Corydoras – Species Profile & Facts

All aquatic environments could benefit from the activity of cleaner fish, even nano tanks. This is where the pygmy Corydoras come in.
These tiny catfish are every aquarist’s wet dream, thanks to their distinct personalities, easy-going temperament, and ease of care.
If you enjoy the presence of catfish but don’t have room to house several of them, pygmy Corydoras are perfect for you.
What is a Pygmy Corydoras?
The pygmy Corydoras is nothing more but a normal catfish, just 3-4 times smaller than your standard Corydoras. These catfish are great for 10-gallon setups and can easily adapt to any freshwater setting, including rich community tanks.
The fish is easily distinguishable by its small, plated, catfish-style body.
Pygmy Corydoras have torpedo-shaped bodies with a brown and white coloring and a black horizontal side-stripe stretching from mouth to tail.
But it’s the fish’s eyes that stand out the most. These catfish have extra-large, completely black eyes and transparent fins to add to their cute appearance.
It’s also worth noting that pygmy Corydoras are shoaling fish, so you can easily keep several of them in the same tank.
Pygmy Corydoras Requirements
If you’ve ever had catfish before, you already know what this species needs. If not, here are some facts to help you out.
Tank Size & Setup
You need at least 10 gallons to accommodate a group of 4-8 pygmy Corydoras. This makes this species ideal for nano setups and offers interesting possibilities when it comes to larger aquariums. The setup should be catfish-specific.
By this, I mean:
- A sandy substrate – Pygmy Corydoras, and catfish in general, spend a lot of time near the substrate. This is to search for food, rest, and even bury themselves in the substrate occasionally. A sand substrate will emulate the fish’s natural habitat and go easy on its skin, given that catfish have sensitive skin, to begin with. Plus, the sand will keep food leftovers from sinking in, allowing the Corydoras to find them easier.
- More plants – Plants are always welcome to any freshwater setting, but they’re much more important in a pygmy Corydoras tank. These fish don’t have any way of holding their ground against larger, more aggressive fish. The addition of live plants will benefit them tremendously, allowing the tiny catfish to use them as hiding spots. They may also occasionally nibble on some plant matter to satisfy their dietary needs. Don’t worry; Corydoras prefer dead plant matter, so they’re unlikely to munch on your live ones.
- Add hiding spots – Live plants serve this purpose quite well, but they’re not enough. Especially since pygmy Corydoras are rather atypical bottom dwellers. In short, these catfish also occasionally swim to the water surface and like to explore their entire habitat. Due to this, you should have a variety of hiding areas throughout the tank to accommodate the fish’s needs. Rocky structures, driftwood, and other aquatic elements are great for this.
Plus, consider investing in a few patches of carpet plants to vary the tank bed a bit. Corydoras love to swim through dwarf hairgrass or similar plant species with narrow and soft leaves.
Water Requirements
Pygmy Corydoras enjoy tropical water conditions with temperatures around 72-80 °F and a pH of 6.0-8.0. Slow water movement and a healthy dose of natural lighting will perfectly complement your Corydoras’ habitat.
Overall, water quality is also important. These fish are rather sensitive to poor water conditions, which will impact not only their health but their immediate behavior as well.
Corydoras have developed an emergency biological system to help them cope with subpar water conditions. Other fish have similar systems, as is the case with the betta and its labyrinth organ.
Unlike bettas, though, pygmy Corydoras showcase the ability to absorb oxygen through their intestinal wall. This is called intestinal breathing, which allows the fish to simply breathe air via its anus.
As alien as this may sound, it’s actually less rare than you might think. Studies have shown that pigs and rats use intestinal breathing to some degree as well.
The pygmy Corydoras has developed this feature to survive in poor water conditions.
So, your Corydoras will swim to the water surface more frequently to breathe if the tank water is poor in oxygen or unclean.
This isn’t ideal, given that intestinal breathing is an emergency system, and it’s nowhere near as effective as the fish’s main breathing system.
So, always keep the tank water in top conditions to prevent your Corydoras from experiencing health problems.
If the water is clean, your catfish won’t exhibit surface breathing behavior at all.
Feeding and Diet
Pygmy Corydoras are your typical bottom-feeder omnivorous fish, which means they’re easy to satisfy. That being said, remember that these catfish require a well-rounded diet to prevent nutritional deficiencies.
Most people think that cleaner fish like Corydoras can easily survive on what the tank provides them with, but this is false. While pygmy Corydoras will happily consume food leftovers from other fish, you should feed them extra to make sure that they’re healthy.
Veggies and animal protein are both necessary, with a plus for the latter. Throw in some brine shrimp, bloodworms, or insect larvae into your fish’s meal plan and sprinkle everything with some fresh veggies for good measure.
Keep in mind that:
- Pygmy Corydoras don’t eat algae – we had to ruin this misconception once and for all
- Pygmy Corydoras cannot survive on an herbivorous diet-only
- Always feed your Corydoras extra in community tanks where other fish will eat their food before it reaches the substrate
Do Pygmy Corydoras Need a Heater?
Yes, they do. In theory, you can keep the fish without a heater, provided that the room temperature is stable.
But this is hardly the case, and frequent temperature fluctuations will cause the catfish to experience visible discomfort.
The heater is even more necessary in a community tank where different fish come with different temperature requirements.
The heater will provide you with the degree of control you need to keep your fish safe and comfortable.
Do Pygmy Corydoras Need a Filter?
Yes, the filter is necessary even in a pygmy Corydoras tank. I would say it’s even more necessary than in a medium-sized or large tank because smaller tanks get dirty faster.
The main idea is to get the right filtration system for the job. Pygmy Corydoras come from environments with fresh, slow-moving water, so they require a clean and well-oxygenated environment to thrive.
Position the filter wisely in the tank and secure it to prevent the fish from going through the intake.
Set the filter’s power properly to avoid excessive water movement which can inconvenience your fish.
Finally, proper tank maintenance is necessary to keep the Corydoras’ habitat clean. Don’t worry, the Corydoras themselves will help with that.
How Much do Pygmy Corydoras Cost?
Pygmy Corydoras are quite pricey for their size. You can get one specimen for about $5-$7 per piece which is impressive for a fish less than an inch in length.
You also need around 8 of them, if not more, for a 10-gallon+ tank. This may not necessarily sound expensive at a first glance, but you have a lot of expenses to consider as a first-time aquarist.
What is the Lifespan of Pygmy Corydoras?
Pygmy Corydoras live approximately 3 years in good conditions, and their lifespan depends heavily on their quality of life.
Provide the Corydoras with a balanced diet, stable water parameters, and a clean environment; they will live longer and more comfortable lives.
How Big do Pygmy Corydoras Get?
Pygmy Corydoras rarely go over 1 inch in length. Females tend to get closer to that mark, while males remain in the 0.7-inch zone. This allows you to differentiate between males and females based on size, but be careful about that.
You can easily mistake juvenile females for adult males if you orient yourself based on size difference alone.
So, you should always look for additional markers when differentiating between Corydoras males and females.
Are Pygmy Corydoras Aggressive?
No, these are not aggressive fish. In fact, pygmy Corydoras are some of the most peaceful tank companions you can get. These fish are harmless and rely on schools to keep themselves safe and comfortable.
This means that you should never keep pygmy Corydoras solo or even in pairs or very small groups.
You need at least 8 individuals to form a compact and supportive catfish group. This will provide the Corydoras with peace of mind and comfort, allowing them to be more active and explore their environment more.
Pygmy Corydoras Tank Mates
Finding the right companions for your pygmy Corydoras is quite the challenge. Not because Corydoras are difficult to integrate into a community, but due to the catfish’s size.
A lot of otherwise peaceful fish can view these tiny Corydoras as prey, so you should handpick their tankmates very carefully.
I recommend species like dwarf gourami, neon tetras, guppies, mollies, Chinese algae eaters, cherry barbs, and even shrimp and snails as compatible companions.
These are unlikely to target your Corydoras due to their similarities in behavior and size.
Even so, you need to make sure that your Corydoras are safe from any adventurous fish species that could target them for bullying or other, more ominous reasons.
In this sense:
- Add more space – You need around 10 gallons for a group of 6-8 pygmy Corydoras, but you need considerably more for a community tank. Make sure that there’s enough space available to accommodate all fish and the necessary tank equipment, decorations, and live plants.
- More decorations and live plants – The goal is to provide your Corydoras with a diverse habitat with plenty of open spaces and hiding areas for refuge. This allows the catfish to retreat when threatened, minimizing the risk and prevalence of bullying and any potential attacks.
- Constant monitoring – Sometimes, even presumably peaceful and tolerant fish can exhibit some aggression. The triggers are numerous, from insufficient space, subpar water quality, insufficient food, sickness, and breeding-related aggression, you name it. So, you should always monitor your fish’s dynamics to make sure that their interactions remain cordial.
Other than that, pygmy Corydoras are great for a well-planned community aquarium.
Are Pygmy Corydoras Good for Beginners?
Yes, pygmy Corydoras are great for beginners. They are easy to maintain, aren’t too demanding in terms of food and water quality, and can adapt to a variety of settings.
That being said, these catfish do have their preferences in terms of housing and overall care routine.
Always remember the following:
- Create a lush aquatic ecosystem – Comfort and safety are 2 of the catfish’s prerogatives. Always have a lot of live plants, rocks, underwater branches, driftwood, and other elements to mimic the catfish’s natural habitat. These tiny swimmers love to navigate their intricate habitat and hide behind decorations.
- Ensure optimal nutrient intake – Many people disregard the catfish’s diet due to their scavenging capabilities. The problem is that Corydoras cannot survive only on what the tank provides them with. This may be the case in the wild, in an open system, but not in a closed system like an aquarium. So, always offer your Corydoras sufficient food to satisfy their nutritional needs.
- Regular monitoring – Pygmy Corydoras aren’t sensitive to any specific freshwater disease, but you should monitor their health regularly anyway. Especially due to the fish’s lifestyle. These fish live in large groups, which means that any contagious disease will quickly turn into a deadly outbreak. Early diagnosis and treatment are fundamental to ensure your fish’s recovery and protect the rest of the population.
How to Tell if Pygmy Corydoras is Male or Female?
Fortunately, you can distinguish between male and female corys quite easily. Size is probably the clearest indicator in
this sense.
Females are close to double in size compared to males. Your typical pygmy Corydoras male can grow up to 0.6-0.7 inches, while females can go to 1 inch in size.
The ventral fins are also different, provided you can actually see them. The fins are triangular in males and rounder in females, giving the appearance of a pouch.
The females use the ‘pouch’ to deposit and carry the eggs pre-mating.
How do Pygmy Corydoras Breed?
Pygmy Corydoras breed easily, but they do require some specific conditions to get into the mood. A protein-rich diet and lower water temperatures are necessary in this sense.
Also, note that pygmy Corydoras are more eager to mate in larger groups since such conditions mimic their natural social system.
The breeding process is rather standard. The cory male will chase the female and fertilize the pouched eggs. The female will then look for a smooth surface to place the sticky eggs, including the tank’s walls. Pygmy females can produce several hundred eggs during the spawning season.
If you plan on breeding your pygmy Corydoras, consider investing in a nursing tank. These catfish have no parental instincts, so they’re likely to eat their own eggs and the resulting fry.
Eggs take several days to hatch, with the fry consuming their egg yolk at first. You can then feed them liquid food until they grow enough to eat whatever the adults are having.
You should give it at least a month before moving the fry to the adult tank. I would go for 2-3 months in case of a community tank where other fish can easily take the fry for food.
Conclusion
Pygmy Corydoras are among the most versatile and useful fish species you can get. They’re great for beginners, since they don’t require any advanced maintenance, and will adapt to any community setup.
Find them the ideal tankmates and craft their habitat to emulate their natural conditions, and your Corydoras will repay you with hundreds of offspring and their eternal gratitude.