1. Preparation:
- Start with a healthy and well-established aquarium with stable water parameters. The recommended water conditions are:
- Temperature: 25-27 degrees Celsius (77-81 degrees Fahrenheit)
- pH: 6.5 to 7.5
- Water hardness: 5 to 10° dGH
- Use a separate breeding tank or a dedicated section in the main tank for spawning. The breeding tank should be around 10 gallons (40 liters) in volume.
2. Selecting the Breeding Pair:
- Select a mature and healthy pair of cardinal tetras. The female should have a plump belly, indicating that she is ready to lay eggs.
- Ideally, the breeding pair should be kept in isolation for a few days before breeding to ensure that they are focused on mating and not distracted by other fish.
3. Setting up the Breeding Tank:
- Ensure the breeding tank is well-filtered and has a gentle water flow.
- Place a fine-mesh breeding net or a spawning mop at the bottom of the tank to collect the eggs. The mesh or mop will prevent the adult tetras from eating the eggs.
- Add some Indian almond leaves or dried peat moss to the water. These materials release tannins that can mimic the natural environment and help the fish feel comfortable.
4. Conditioning the Pair:
- Provide a varied and nutritious diet to the breeding pair. Live or frozen foods, such as brine shrimp, daphnia, and bloodworms, are recommended.
- Gradually increase the water temperature in the breeding tank by a few degrees Celsius (a few degrees Fahrenheit) over a few days to simulate the rainy season in their natural habitat.
5. Spawning:
- Introduce the breeding pair into the prepared breeding tank.
- If the conditions are suitable and the pair is ready, they will engage in courtship behavior. The male will display his fins and chase the female. The female will deposit her eggs among the breeding net or spawning mop.
- The male will fertilize the eggs as the female lays them.
6. Post-Spawning Care:
- After spawning, remove the adult tetras from the breeding tank to prevent them from eating the eggs.
- Maintain the water conditions and temperature as they were during spawning.
- The eggs will hatch within 24 to 48 hours.
7. Feeding the Fry:
- Once the fry hatches, feed them with infusoria or commercially available fry food.
- Gradually increase the food size as the fry grow.
8. Rearing the Fry:
- Keep the fry tank clean and well-maintained to prevent disease and ensure healthy growth.
- As the fry grow, you can gradually transition them to a community tank or larger aquarium.
Remember that breeding cardinal tetras requires patience and attention to detail, and the success rate may vary depending on various factors. However, following this step-by-step guide can help increase your chances of successfully breeding these vibrant tetras.