Cardinal Tetra is one of the famous aquarium fish kept by most aquarist. The fish itself are come with a very striking coloration which makes the fish photogenic. This is why the fish are unique and makes most aquarist would like to start breeding cardinal tetras in home aquarium.

Discus Fish

Discus Fish

Breeding the fish would be a great challenge but still is possible to breed them in breeding tank. The fish are lovely but it is hard to keep them for a long term comparing with other hardy freshwater fish. Most aquarist kept cardinal tetras together with discus fish as tank mates and the fish are large enough that won’t be a food for the Discus fish.


Cardinal Tetra are originate in northern South America in the black water river of Orinoco and Rio Negro. Most of the fish are captured in the wild during dry season which housing them in the aquarium require mimic the nature where the fish belong. The fish feed themselves with live worm and crustaceans.

If you are serious of breeding cardinal tetras in home aquarium there are certain priority which you may need to know to make sure the breeding success. The female are slightly bigger than the male which you will notice the size of the fish. The female body would look rounder compare with the male cardinal tetra.

Setting Up For Breeding Tank

Cardinal Tetras are shoaling fish which it is recommend keeping them in a 6 to 10 fishes. Prepare a breeding tank with a minimum size of 10 gallon. If the tank use to breeding before, cycle the tank before breeding cardinal tetra. The fish usually breed in a group during in the wild but you can breed them in pair. As preparing the breeding tank, make sure the tank are 10cm deep and install a sponge filter.

The spawning process require the water to be soft and stable under the tank to prevent the eggs of the fish floating. Another important tips is change the chemical composition of the water carefully. Perform a water change every week to maintain the suitable water parameter for the fish to breed.

Set the pH level around 4.5 to 5 and the ideal water temperature to maintain in the breeding tank should be 28°C. You can add spawning mop into breeding tank which the fish can lay it eggs on. If breeding the cardinal tetra only, add substrate to protect the eggs because acidic water also could harm the eggs.

You can add sterilized peat moss into the breeding tank. Before adding the peat moss, soak it with water until the peat moss sink. Adding live plant such as Java moss into the breeding tank which it can provide cover for the new born fry.

Breeding Process

male cardinal tetra

male cardinal tetra

After the setup is done, you are reading for breeding cardinal tetras. The fish can breed in pair or group place in a different tank which you can feed the male and female with flakes, frozen and live food include live white worm and blood worm for 1 to 2 week. Place the male and female into the breeding tank and do not feed them during the spawning.

The male will pursue the female cardinal to the live plants when they are ready to breed. If the female accept the male, the female will swim along with the male. The male cardinal will release the sperm and the female release it egg in the same time.


female cardinal tetra

female cardinal tetra

Remove the parent once the egg are visible in the tank and do not exposed the egg towards any light. The eggs will hatch in 2 to 3 days. The eggs dies when it exposed to any illumination. Some breeders keep the adult together with the eggs and new born fry. It is nothing wrong with it but I advise keeping the fry separately with the adult.

The newborn fry are sensitive with light which the tank should keep in low light condition for at least a week. Slowly introduce the fry by increasing the lighting level of the tank. Feed the new born cardinal fry with infusoria or any commercial fry food. Feed the fry with baby brine shrimp, micro worms, and well crushed flakes food after a few week.

Feed the fry twice a day with 1 or 2 drop of eyedropper. Change small amount of water in the tank after 2 or 3 days and add the water with the same chemistry. Use airstone on the end of the length or airline turbine to prevent the fry siphoned out of the water during performing water change.

The fry takes 8 to 10 week to grow and the fish are not color up. They reach it sexually maturity in 8 month times. The fish grow real slow which required a lot of patience. I hope you success in breeding cardinal tetras after reading this post and all the best. Cheers!