Under the right conditions, Cory Cats are actually very easy to breed, and a lot of the time people will have them breed in their community tank without them doing much. Here are some things to consider if you’re thinking of breeding cory cats or if you have a surprise batch of cory cat eggs.
- Cory cats are schooling fish, and often need a school of around 6 to feel secure and breed.
- Cory cats are egg layers and will scatter their eggs on the glass and decorations in your aquarium.
- Cory cat fry are really small and because of that eat really small foods.
- You will need a separate container for the fry and also a grow out aquarium as the catfish get bigger.
- Cory cats will lay anywhere between 20 and 100 eggs at a time.
- Cory cats can spawn every week.
How to Make Your Cory Cats Spawn?
I personally have not tried these methods because my cory cats spawn every week without me doing anything, but I talked to people who have purposefully spawned their cory cats. If you are trying to breed your cory cats, I would recommend setting up a separate breeding tank just for the cory cats. Once that tank is set up, you want to increase their feedings and feed them items like frozen bloodworms. Once you have done this for a couple of weeks, you should do a large water change in the aquarium, around 50%. You then replace the water with cooler water. You should do this every week and keeping the water cooler in between as well by lowering your heater. The goal is to bring the temperature down around 65 degrees F. This is the reason you may want to set up a separate aquarium, because many of the tropical fish we keep can’t tolerate the colder temperatures needed to trigger spawning.
Eventually, you will see small eggs scattered in the aquarium, as seen in the picture to the right. Some people recommend leaving the eggs in the tank and removing the parents so they don’t eat the eggs; however I decided to remove the eggs instead. Besides the fact that my cory cats bred in a community tank, I wanted to remove the eggs so that when the cory cat fry hatched they would be in a smaller container and easier to feed. Eggs on the glass are easy to remove. I used a razor blade to slide them off. The eggs will sink when they aren’t attached to the glass, so I originally placed a fish net under the eggs as I scraped them off. This worked pretty well, but I later found that using a turkey baster was much easier to collect the eggs.
Incubating and Hatching the Eggs
Once I had the eggs removed from the glass, I transferred them to a separate holding container. For this, I took a five gallon aquarium, which serves as the grow-out container as they get bigger, and I put a small plastic container at the top of it. I didn’t have any substrate in the container where they eggs were. The reason I didn’t just use the plastic by itself is, I didn’t want to have a heater in a small plastic container and risk melting it or something else. The water temperature was much more stable in the grow-out container since it was larger. This helped stabilize the hatching container temperature as well. I then ran an airline tube to help circulate the water. I also used a turkey baster to move the water around once or twice a day. Some of the eggs may turn white while you are incubating them. These are unfertilized eggs and you should do your best to remove them if you see them to prevent fungus from growing. I kept this aquarium around 78 degrees and the eggs hatched between 2-3 days. The baby catfish are very tiny and will look like they have a big stomach, that is their yolk sac. They won’t need to eat immediately since they yolk sac provides the food they need for the first day or so. I transferred the newly hatched fry out of the plastic tub to a larger container.
Mini-Grow Out Tank
The mini-grow out tank I set up like a mini aquarium. I had a layer of sand, enough to cover the bottom, and I put in some java moss as well. I also ran an air stone for aeration, but no motorized filters. This mini-grow out tank was put in the larger grow out tank again so the fish wouldn’t have direct contact with the heater.
The reason I have the fry in such a small tank to start (about 1/2 gallon), is to have a higher concentrate of food for them. If I put the fry in a 10 gallon or even a 5 gallon to start, I would need to feed a lot more just to get enough concentration of brine shrimp for the fish to be adequately fed. By keeping them in a small tank for a couple of weeks you can closely monitor them and make sure they are growing.
It’s important that the grow-out tank has a lid as well. This is so the air is the same temperature as the water and has a high humidity. Cory cats will actually take gulps of air on occasion, and if the humidity is too low, this could harm your fry.
Feeding Newly Hatched Cory Cats
Since the newly hatched cory cats are so small, I fed them newly hatched brine shrimp. If you have never hatched brine shrimp before, it’s very easy, and it takes around 24 hours. I would recommend starting the brine shrimp hatchery after two days of incubating the eggs. That will give time for the brine shrimp to hatch if they take a little longer than 24 hours.
After about a week or so, you can start mixing in finely crushed flake food with the live brine shrimp. You may need to hatch the brine shrimp a couple of times during the first week to make sure you have enough food. I would recommend feeding the catfish fry 2-3 times each day. The brine shrimp will live in the water for a few hours, so you can add a few squirts of them so the fry can eat throughout the day. I would recommend making sure they almost always have access to food in the beginning, which is why you need to perform water changes.
It’s important to keep the water clean, and this can be difficult with the amount of feedings. The fish will be too small for you to use a siphon to clean the water, so what I did was remove some of the water using a cup every other day. I would then replace it using the water from the larger tank. This way I knew it was the exact same temperature so I wouldn’t have to worry about shocking the fish.
After about a month, I transferred the catfish fry to the 5 gallon aquarium to grow out. I kept them in there with a sponge filter until I moved them to a larger grow-out tank a month later with a mechanical filter. At this point the catfish are a few months old and are get large enough to fend for themselves in a community tank.