Corydoras Breeding: How Often Do Cory Catfish Lay Eggs?

Last Updated on September 24, 2021 by cmoarz

Have you considered breeding your corydoras (armored catfish)? There’s a lot of information available to help you get started for sure., Did you know that Cory catfish come in around 150 distinct species, with their own set of characteristics and breeding requirements? That’s a lot of information to sift through. Especially just to get generic answers like “How often do cory catfish lay eggs?”

The purpose of this article is to clear out some of the clutter and get right to the point about cory catfish eggs.

How often do cory catfish lay eggs?

If cared for correctly, Corydoras can lay eggs every week. Typically, Corydoras lay between ten and fifteen eggs at a time per batch. Some corydoras will lay their eggs in the sand, While others will stick them to glass and plants. Each batch will take approximately 3-5 days to hatch.

Can you increase the number of eggs a female will lay at once?

Yes, Actually! By keeping the water conditions in the separate breeding tank or community tank the correct water temperature and water chemistry and other water parameters, as well as slow-moving waters, While increasing nutritional intake of the female cory catfish she will lay more eggs in each clutch. The tank should also be filtered properly, a good sponge filter is what I recommend.

All of these things will give you bigger clutches as well as to encourage breeding more fervently.

While it won’t be a huge increase in the number of cory eggs, it could increase by as much as 5+ extra eggs, which in turn is 5 more corydoras catfish baby fish fry. How many eggs they lay also factors in genetic predisposition and health and age.

How can I tell if my corydoras have laid fertile eggs or infertile eggs?

It’s pretty easy to tell if your cory cats are laying eggs that are fertile. Fertile eggs will have a brownish beige color to them and will hatch within 5 days. Almost like your looking at a light cup of brown tea. Unfertilized eggs will start off as off-white and continue to become more and more white as time goes on. These unfertilized eggs will not hatch.

Fertile eggs should be placed near an air pump and airstone, Or rather, An air stone should be placed near the eggs. This helps the eggs hatch while preventing them from develop fungus.

To ensure you get as little infertile clutches as possible, keep at least six cory catfish per tank. This will increase the odds of having male and female corydoras breeding pairs. As social schooling fish, this will also increase their happiness level and encourage them to lay.

You can also move your eggs to a separate container where you intend on raising the fry. This is a more advanced thing to do as it takes a lot of skill to move the eggs without damaging them. It should be noted that sometimes cory catfish will eat their own eggs and fry.

This goes for other fish, as well as other bottom dwellers as well. So it’s always a good idea to have a new tank ready to scoop your fry into once they hatch and to remove them from the main tank whenever possible.

If that’s not an option and you have to keep them in the same tank, be sure the main tank or breeding tank has plenty of hiding places for the fry. Hiding places will ensure the safety of the fish assuming they don’t wander out and get eaten by other tank mates.

No one ever said breeding cory catfish was easy!

In fact, it’s one of the more difficult to breed species of fish!

Taking care of the fry once the fertilized eggs have hatched

After the hatching period has ended, it’s a good idea to move the fry into a new fish tank you’ve set up for fry. While this step is optional, it can be a bit easier to manage them and keep them fed and safe. A small tank is more than enough as long as it has the proper conditions and filtration. A sponge filter will prevent fry from getting sucked in.

If you haven’t set up a fry tank yet, It’s pretty straightforward. Add some java moss, a filter, some plants, and, if required, a heater. You can even place some cherry shrimp in with the fry, as they usually won’t eat them (usually!). These will prove as additional tank cleaners.

I talked about moving the eggs earlier, That might be easier for some people than trying to catch active fry. To do that, simply slide a razor blade under the eggs to detach them from the glass of the fish tank. You need to be super careful here not to damage them.

Now it’s time to start feeding them

Live brine shrimp are best. Newly hatched brine shrimp are ideal because they’re so tiny. Cory catfish fry needs to eat every single day, multiple times a day to stay healthy and continue growing. If they miss even 1 day of feeding they can die.

Other small live foods such as daphnia can be given as well.

The first week will be the toughest, after that the ones left alive are likely to make it into adulthood.

Additional information that may still be important to know

In the wild, cory catfish lay eggs during the rainy season. This is when small droplets of cold water hit the surface of the river and encouraged breeding season. Spawning is pretty straightforward, and most will lay their eggs against rocks, logs, and in the sand itself.

During spawning, females corydoras catfish lay their eggs while the male corydoras catfish will ‘squirt’ their… ‘Spawning fun time juices’ over the eggs. I’d have said seed, but that doesn’t sound half as fun, now does it?

As I said, No one ever said breeding cory catfish is easy. In fact, it’s very difficult to match the proper water parameters and conditions necessary to induce spawning and mimick their breeding season. However, once you finally get them to breed the first time, You will understand how to get the females “in the mood” so to say. Good luck!


Owner of and also owner of actual Aquarium Gravel believe it or not! ;). Setting up beautiful aquarium sceneries and habitats since I was very young. Enjoy!