Goldfish make wonderful pets and are easy to maintain as well. They do not need much attention and make ideal pets for those with a busy lifestyle. They belong to the family Carassius Auratus, and are of different varieties like 'comet', 'shubunkins', 'oranda', 'watkins', 'telescope', etc. It is best to keep them in fish tanks or aquariums rather than keeping them in bowls, as they require a little more space compared to other pet fish. Breeding them is an easy process, but you need to know some of the basics before you can try it.
Choosing a Goldfish
Goldfish can be bred twice a year and need warm temperatures for breeding. Those which are two years or older are ideal for breeding, but those that are five to six years old will be the best. While choosing the specimens, choose those that are of good quality and assess them according to their color, size, and structure of their body and fins. Choose a higher ratio of males, like two males to one female, for better breeding chances.
Determining the Gender
Determining the gender is a bit difficult and this can be done accurately only when the fish reach the spawning stage. A female has a protruding, heavier abdomen and is plumper, while a male develops a breeding tubercle on the gills when it reaches the spawning condition. A male also has a slight white bump on its head which can be easily spotted. You may find it difficult to determine the gender initially, but it will be fairly easier with practice. You can also seek the help of a professional breeder to get a hang of this process.
Preparing for Spawning
You can start preparing the fish for breeding in early spring, right after winter. The first step would be to clean the fish. For this, you will need to add a cleaning solution which can be made by mixing 6 drops of copper sulfate, one measure of terramycin, and 80 drops of formaldehyde in 4 gallons of water. Add this solution to the water in the aquarium and let the fish remain in it for around 20 minutes. Then, remove them and place them in a container of clean water. You can then start preparing the aquarium for spawning.
You need to create a natural spawning environment. This can be done by cleaning 20% of the water daily and replacing it with tap water. You can also use a water conditioner after cleaning the water. Add spawning props like natural plants, artificial or coconut fibers, spawning mops, etc. in the tank. Make sure that the water temperature is around 26°C, which is the ideal temperature for breeding. Place the goldfish back into the tank, and keep feeding them at regular intervals so that the female develops healthy eggs and the males develop 'milt', a substance required to fertilize the eggs.
When the fish are ready for mating, you will be able to observe a 'spawning chase' that is characterized by the male swimming close to the female's abdomen for a long time. This process usually takes place during the mornings and the fish will be seen swimming in batches. When the female is ready, she releases the eggs and the males deposit the milt over the eggs to fertilize them. The female releases around five hundred to a thousand eggs at one time. Note that goldfish eat their eggs and so the parents or the eggs should be removed from the tank. If you remove the eggs, they need to be washed in water that has the same temperature as that in the tank. They should then be placed in a 20 gallon tank which has water up to six inches, and its temperature should be around 21°C.
Hatching of the Eggs
The eggs that look very clear are the ones that are most fertile. You should observe them regularly, as the ones that are not very fertile are susceptible to fungal infections that may also spread to the healthy eggs. After they have hatched, they will have a translucent yolk sac which will make them sink to the bottom of the tank. This is a common phenomenon. After the yolk sac is absorbed, the baby fish obtain an air bladder and start swimming. At this stage, you can start feeding them commercially-available food.
Once you have gained a substantial amount of experience in goldfish breeding, you can take it up as a hobby or even become a professional breeder.