Pygmy Cory: A Delightful Introduction to These Tiny Aquatic Pets

The Pygmy Cory, scientifically known as Corydoras pygmaeus, is a charming little freshwater fish that many aquarists adore. Hailing from the Madeira River basin in Brazil, these tiny creatures are known for their unique swimming style and small size, making them a popular option for nano aquariums.

As you learn more about the Pygmy Cory, you’ll discover that they are relatively low-maintenance and adaptable, making them a fantastic addition to your aquatic community. In the upcoming sections, you’ll learn about their ideal tank mates, diet, and other details that will help ensure a happy and healthy life for your new fishy friends.

Species Profile

Here is a brief overview of the Pygmy Cory:

Property Information
Scientific name Corydoras pygmaeus
Common names Pygmy Cory, Pygmy Catfish
Distribution South America (Ecuador, Brazil)
Size Up to 1.2 inches (3 cm)
Lifespan 3-4 years
Diet Omnivore
Temperament Peaceful, sociable
Minimum tank size 10 gallons
Temperature 72-79°F (22-26°C)
pH 6.0-7.5
Water hardness 2-15 dKH
Care level Easy
Filtration/Water Flow Moderate
Water type Freshwater
Breeding Egg-layer
Breeding difficulty Moderate
Compatibility Community aquariums

Pygmy Cory is a small and peaceful freshwater catfish that originates from South America. They can grow up to 1.2 inches and have a lifespan of 3-4 years.

As omnivores, they consume a variety of foods, including high-quality flakes or pellets, as well as frozen or live foods such as brine shrimp and bloodworms. The Pygmy Cory is an active and social species, making them great additions to community aquariums.

When setting up your tank, ensure you maintain a temperature between 72°F and 79°F, pH levels from 6.0 to 7.5, and a water hardness of 2-15 dKH. A minimum tank size of 10 gallons is necessary to provide them enough space to swim comfortably. Moderate water flow and filtration are essential to maintain clean and healthy living conditions.

Breeding Pygmy Cory is moderately difficult; eggs are laid by females and need a separate, well-maintained tank for hatching. They are compatible with other peaceful tank mates, making them a great choice for a friendly community aquarium.

Pygmy Cory Basics

Origins and Natural Habitat

Pygmy Corys (Corydoras pygmaeus) are small freshwater fish that originate from the Madeira River basin in Brazil, although populations are found across South America. In their natural habitat, they are accustomed to a pH range of 6.4-7.5 and moderately soft water.

Size and Shape

Your Pygmy Cory will be a petite fish; it usually reaches a maximum size of 0.8 to 1.1 inches (2-3 cm). Their bodies are slim, and they are equipped with whisker-like barbels around their mouth, helping them find food by probing the substrate.

Color and Markings

The Pygmy Cory has a pale tan or olive color body, with a distinctive thin, horizontal black stripe running the length of the body from the nose to the tail fin. This feature makes it easy to identify them among other species in the tank.


When properly cared for in your aquarium, Pygmy Corys can live up to 4 years. Maintaining the right water conditions, diet, and tank environment will significantly contribute to their longevity.

Diet and Feeding

Feeding your Pygmy Cory properly is essential for their health and well-being. These tiny fish are omnivores, so they require a varied diet to fulfill their nutritional needs. Here are some tips on what and how to feed Pygmy Corydoras:

  • Incorporate fresh and frozen veggies into their diet, as they enjoy a bit of greens now and then.
  • Provide a balanced mix of animal protein sources like brine shrimp, mosquito larvae, and bloodworms.
  • Use algae pellets and wafers as an additional source of nutrition.
  • Supply store-bought pellets and flakes, ensuring they meet the nutritional requirements of the fish.

It’s essential to keep an eye on how much you’re feeding them to avoid overfeeding. Feed your Pygmy Cory two to three times a day with small amounts they can consume within a few minutes. Maintain a clean and healthy tank environment by removing any uneaten food after feeding time.

Behavior and Temperament

Pygmy Cory are well-behaved, peaceful fish that are perfect for community aquariums. They enjoy the company of their own species, so it’s best to keep them in groups of at least six. This allows them to exhibit their natural shoaling behavior, swimming together in harmony in the lower and mid-levels of the tank.

Although these fish are generally bottom-dwellers, they occasionally venture upwards, showing off their playful side. It’s essential to provide them with hiding spots, like plants, rocks, or caves for balanced mental stimulation.

As facultative air breathers, Pygmy Cory have an exceptional ability to draw oxygen from the air. This adaptation comes in handy if they find themselves in oxygen-deprived situations.

When setting up your tank, keep in mind to avoid overcrowding the mid-levels with other species. With proper care and observation, you’ll be able to enjoy watching your Pygmy Cory thrive in a social environment.

Care and Tank Requirements

In this section, you will find information on the care and tank requirements for your Pygmy Cory. We will discuss tank size, water parameters (temperature and pH), tank setup and decorations, as well as filtration and aeration.

Tank Size

As a small fish species, Pygmy Cory catfish do not require a very large tank. A minimum tank size of 10 gallons should suffice for a small group of these fish. Keep in mind, they thrive when kept in groups of at least 6 to 10 individuals, so a larger tank is recommended if you have the space.

Water Parameters (Temperature and pH)

  • Temperature: Pygmy Cory catfish prefer warmer water, with a temperature range of 72°F to 79°F (22°C to 26°C). Consistency in temperature is important for their well-being.
  • pH: They can tolerate a pH range between 6.0 and 7.5. However, a stable pH around 7.0 is considered ideal for these fish.

Tank Setup and Decorations

To create a comfortable and natural habitat for your Pygmy Cory, consider the following tank setup and decoration tips:

  1. Substrate: Soft sand is the best choice for the substrate, as it’s gentle on their delicate barbels and fins. Avoid gravel or sharp-edged materials that can cause injury.
  2. Plants: Include live plants in your tank to provide hiding spots and improve water quality. Plants like Java moss, Anubias, and Amazon swords are all suitable choices.
  3. Hiding Spots: Add decorations such as caves, driftwood, and rocks to create hiding spots for your Pygmy Cory. This will help them feel secure and promote their natural behavior.
  4. Lighting: Soft, subdued lighting is recommended for creating a stress-free environment. Keep in mind that bright lights can make your fish feel exposed and uncomfortable.

Filtration and Aeration

Proper filtration and aeration are essential for maintaining a healthy environment for your Pygmy Cory. Here are some guidelines:

  • Filtration: Choose a filter that is adequate for the size of your tank and provides mechanical, chemical, and biological filtration. A hang-on-back (HOB) filter or sponge filter are reliable options.
  • Aeration: Proper oxygenation is crucial for your fish’s well-being. Adding an air stone or using a filter that produces surface agitation can help maintain sufficient oxygen levels in your tank.

By taking care of these care and tank requirements, you will be providing your Pygmy Cory with an environment where they can thrive and display their natural behaviors.

Suitable Tank Mates

Pygmy Corys are peaceful fish that prefer to live with similarly sized species that are smaller than an inch. Since they can be seen as prey by larger and more assertive species, it’s essential to choose tank mates wisely. You can also consider shrimp and snails as compatible tank mates.

Some good tank mates for Pygmy Cory include:

  • Neon Tetra
  • Ember Tetra
  • Dwarf Gourami
  • Zebra Danio
  • Apistogramma
  • Kuhli Loach
  • Otocinclus
  • Guppies
  • Molly Fish
  • Cherry Barb
  • Hatchetfish
  • Chinese Algae Eater

To create an ideal environment, it’s recommended that you keep a shoaling group of at least eight Pygmy Corys. When kept alone, they may exhibit stress symptoms, spending most of their time hiding and displaying sporadic behavior. In a larger group, they gain confidence and show playful behavior, resulting in a more desirable community fish experience.

However, it’s essential to avoid keeping Pygmy Corys with betta fish, as bettas are known for their aggressiveness towards them.

Breeding Process

Breeding Pygmy Cory catfish can be an enjoyable experience, and it is relatively easy to achieve. Often, these fish breed naturally when they are part of a large group in a well-maintained tank.

To encourage the spawning process, provide your Pygmy Cory with a protein-rich diet and gradually lower the water temperature to simulate breeding season conditions. As a female retains a few eggs, she will wait for the male’s fertilization before depositing the eggs on smooth surfaces, such as the glass walls of the aquarium. She will repeat this process, resulting in the laying of around a hundred eggs.

After the female Pygmy Cory finishes depositing her eggs, it’s crucial to remove all adult fish from the tank. Pygmy Cory catfish do not exhibit parental behavior and may consume the eggs and fry if left with them.

Keep a close watch on the developing eggs, removing any that show signs of fungus. Fungal infections can quickly spread and harm other eggs if not dealt with promptly. In time, the fry will hatch and become free-swimming. Initially, they will feed on their egg sac.

Ensure you provide appropriate tiny foods like infusoria and baby brine shrimp to the fry, which will help in their growth process. Once they are big enough, they can consume the same foods as their parents. With proper care and attention, your Pygmy Cory population will flourish.

Common Diseases and Treatments

Red Blotch Disease is a common illness that Pygmy Cory catfish can be more susceptible to than other fish. To treat this disease, monitor your tank conditions, such as temperature and pH levels, to ensure they are stable and within the recommended range.

In addition to Red Blotch Disease, Pygmy Corys are also vulnerable to common freshwater illnesses. To keep your Pygmy Corys healthy, always maintain a clean environment, perform regular water changes, and avoid overfeeding. If you notice any signs of disease, such as lethargy or changes in appearance, consult an aquarium expert for advice on the appropriate treatment.

Remember, prevention is better than cure. By maintaining a healthy habitat and monitoring your fish closely, you can minimize the risk of disease and keep your Pygmy Corys thriving in your aquarium.

Frequently Asked Questions

How big do pygmy corys get?

Pygmy corys are small fish, usually growing to about 1 to 1.5 inches in size. They have a distinctive catfish-style body, with a plated appearance that makes them stand out.

What do pygmy corys eat?

Pygmy corys are not picky eaters and can thrive on a variety of foods. They enjoy eating sinking pellets, flakes, and small frozen or live foods such as brine shrimp and daphnia. Make sure to provide a well-balanced diet to keep them healthy and active.

How many pygmy corydoras should be kept together?

Pygmy corys are social fish and do best when kept in groups of at least 6 to 10. They enjoy being in shoals and feel more secure in numbers. Keeping them in groups also adds to their interesting behavior, making your fish tank a lively and engaging environment.

How many pygmy corys in a 10-gallon?

A 10-gallon tank can comfortably accommodate a group of 6 to 10 pygmy corys. These small catfish adapt well in smaller, well-planted tanks. Remember to provide ample hiding places and maintain good water quality to keep your pygmy corys happy and healthy.

What are the smallest Corydoras?

Pygmy corys (Corydoras pygmaeus) are among the smallest species of Corydoras. They typically reach up to 1 or 1.5 inches in size. Another closely related species is the dwarf cory (Corydoras hastatus), which also remains quite small, measuring around 1.2 inches in length. Both species make excellent additions to nano tanks and smaller aquariums.