Breeding Cardinal Tetras: A Step-by-Step Guide

Cardinal tetras are popular freshwater fish that you can breed in captivity for years. Breeding cardinal tetras are relatively simple, but they require patience and dedication to the process. If you want to reproduce this fish, you should know a few things about breeding Cardinal tetras.

Breeding Cardinal tetras is not tricky, but it does require some time and patience. It also helps to have the right equipment and supplies. Breeding your cardinal tetras starts with setting up their breeding tank. After that, you need to get your fish ready for breeding. Finally, let them pair up and breed before you can collect the eggs.

There are a lot of steps in breeding your Cardinal tetras. It can be pretty tedious, but it is worth the effort! If you follow these steps and pay close attention to the details, you should have a successful spawn of cardinal tetra fish babies.

Is Breeding Cardinal Tetras Easy?

Breeding Cardinal Tetras can be difficult. First, you have to get your water chemistry right, provide good filtration, and plenty of plants for the parents to build a bubble nest in.

Breeding Cardinal tetras is something that you can do easily in the home aquarium with some essential equipment and knowledge. Nevertheless, it’s gratifying when it works, so let’s start breeding our Cardinals.

Despite breeding needing a lot of patience, you can still breed Cardinal Tetras in a small aquarium if you have an established tank with plants and good water quality.

How Do Cardinal Tetras Reproduce?

The reproduction of Cardinal tetras does not differ much from other fish that live in groups. However, Cardinal tetras reproduce through conspecific mating. It means that they will produce with members of their kind.

The males will build a bubble nest on top of vegetation or somewhere else with a slight current, so they don’t have to work as hard against the water flow when keeping their eggs afloat. They may also attach the bubble nest to plants to not sweep away afterward.

The male will then court a female Cardinal tetra into his territory, where he will fertilize her eggs by releasing sperm over top of them. Unlike other fish, cardinal tetras do not need any courtship to breed successfully.

Male and Female Cardinal Tetra Reproduction

The female is responsible for carrying the eggs through fertilization. She must be strong enough to swim with them, which can take a toll on her body if she does not eat well. They are egg-layers and place their eggs in small areas that allow oxygenated water to flow over them. You can usually put them in the roots of plants or on leaves.

Cardinal Tetras Spawning Time Frame

The breeding season can vary depending upon a geographical location. But it is typically during April and May when water levels rise due to warmer temperatures. After mating with a male cardinal tetra responsible for fertilization, the female will lay her eggs.

Cardinal Tetra Egg Development Timespan

The eggs will incubate inside the female’s mouth until they hatch about a week later due to the temperature of her mouth and gills. They hatch as fry at this time because it allows them to remain in their natural habitat longer during development.

Cardinal Tetra Fry Development Periods of Time

The fry will develop their fins within the first month and look like miniature versions of adult cardinal tetras. They eat finely crushed flakes or brine shrimp after two weeks in water with a pH level between six and eight. Cardinal tetra fry can also eat infusoria and algae, naturally present in the tanks.

Can Breeding Cardinal Tetras In-Home Be Possible?

Yes, it is possible to breed cardinals in a home aquarium. These fish are easy-going and do not need a large aquarium to breed. In addition, Cardinals will mate with other fish species, such as neon tetras and rummy-nose tetras.

As mentioned before, the most crucial step in breeding is setting up a proper tank for your cardinals. It means having live plants or well-planted fake ones. Plants are critical to a successful breeding tank as the cardinals will use them for mating and shelter.

What Do You Need To Breed Cardinals?

Before you start, read below about what every breeder should have before they begin:

Breeding Net

A small, fine mesh net with a handle is perfect for catching young fish from your aquarium.

Breeding Traps

A breeding trap is like a net but has walls that guide the cardinal into the middle. It will help you to breed your cardinals without having them scatter everywhere or escaping before mating can occur.

Separate Tank For Parents

Before starting, it’s vital to have an extra aquarium ready for housing your breeder cardinals. This tank should be about 30 gallons and contain all the same equipment (heater, filter) as your main breeding tank to make things easier for you down the line.

Breeding Mop Or Cotton Wool

Mops are perfect for keeping the eggs in one place until they hatch. Then, you can either buy them online or make them by balling up some cotton wool.


Having a thermometer in your breeding tank is very important as it will help you keep track of the temperature. It would be best to keep it between 75 and 80 degrees Fahrenheit (24 – 27° Celsius).

Tank With Live Plants Or Fake Plants

You’ll need to have some live plants or well-planted fake ones in the tank for your cardinals. The point of this is to use them as shelter and mate with each other. If you don’t provide these, they will most likely not breed at all because it’s an essential part of their lives.

pH Testing Kit

It is essential so that your water doesn’t become too acidic or alkaline. Therefore, you need to test the pH of your breeding tank regularly with a testing kit available at most pet stores. The ideal range is between pH of about 70 and 80.

Water Conditioner

So that you don’t shock the fish, it’s essential to use a water conditioner before adding your cardinals to their new tank or moving them from one tank to another (such as for feeding).

Breeding Your Cardinal Tetras: Step By Step Guide

Once you set up everything, it’s time to choose a breeding pair. If you don’t already have some cardinal tetras in your tank, now is the time to buy one or two males and several females. It will give them all someone to mate with and ensure that you won’t end up with a bunch of babies.

The basic steps for breeding cardinal tetras are as follows:

Step One: Choose A Breeding Pair

The first step is to choose a breeding pair. If you don’t already have some cardinal tetra in your tank, it’s time to buy one or two males and several females. It will give them all someone to mate with and ensure that you won’t end up with a bunch of babies.

Step Two: Set-Up Breeding Tank

The next step is to set up the tank for breeding. It would help if you had a separate aquarium or container to place your new family. So, their parents and other fish do not eat them in the main tank.

It needs to be at least five gallons of water per cardinal tetra, but larger tanks are better if possible. Ensure there is no gravel, plants, or other objects in the tank.

Step Three: Separate Breeding Pair

Put your breeding pair into their new home and leave them alone for a few weeks so that they get familiar with it. They will need time before they are ready to breed, so don’t worry if you haven’t seen any signs of eggs yet. It may take up to three weeks, but you can try again at another time even if they haven’t bred after that.

Step Four: Introduce Male To Female

Once the female is visibly pregnant and her belly starts swelling, it’s time for the fourth step—introducing a male. Put him in with your breeding pair (the female should be more significant than him), and make sure they are the only cardinal tetras in the tank.

Step Five: Eggs

If you didn’t see your pair mate before, it’s time for some detective skills to find out if there have been any babies. If everything has worked fine, you will soon notice tiny baby cardinal tetras swimming around the tank. It’s best to leave their parents in there for another week. Then remove the female and all of her babies back into your main tank.

Final Step: Remove Parents

The last step is removing any adults from the breeding aquarium, leaving only eggs if possible. The eggs should hatch within a few days, and your breeding cardinal tetras then grow fully.


In conclusion, cardinal tetras are a beautiful species of fish that you can breed in your home aquarium. You can generate them as early as the age of six months. But I wouldn’t try producing them until at least nine or ten months old. They will also need a vast tank – once they reach eight weeks old. So, you will need to transfer them to a tank at least 50 gallons in size.

You will also need fine substrate, which is vital for the eggs to stick. The breeding process itself does not take too much work – remove any aggressive fish from the tank and do daily water changes of 25% every day until you see fry (babies) swimming around on their own.

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