My Experience in Breeding Goldfish

By Adip Sajjan-Raj
From the May 2000 "Infoaquaria", Aquarist Society of Bangalore, India
Aquarticles

I looked around the Aquarium Exhibition held last year (May 1999) and decided to rear some fish. After much thought I settled on goldfish because of their graceful form.

I picked a few goldfish and brought them home. I set up a 150 litre aquarium for them, and looked after them with care. Now, after a year, they are 4" long.

One day as usual I switched on the light of the aquarium at 6.30 a.m. and noticed much activity which made me sit straight and observe. I saw a goldfish chasing another, and to my surprise I saw goldfish eggs all over the tank and on the plants.

I immediately transferred these two fish into another aerated tank and added some floating plants and leaves. As soon as the plants were put in I saw the male fish chasing the female and then coaxing her to rise to the surface of the tank. He then pressed the female's stomach with his own stomach. This made the female release eggs and the male release sperm. Most of the eggs got stuck to plants on the surface of the water and some fell to the bottom of the tank. The egg laying process lasted about 2-3 hours, after which I removed the parents from the tank.

After 36 hours I could see the eyes of the fry which were forming inside the eggs. A few of the eggs became opaque which showed they were unfertilised. They started to develop hairy fungus. I used some methylene blue to prevent the fungus from spreading to the fertilised eggs.

After about 48 hours I saw the fry hatching out of the eggs and clinging onto the plants. All the newborn fry had yolk sacs attached.

After 24 more hours all the fertilised eggs had hatched and the fry were now clinging onto the aquarium glass. I did not feed them anything as they had their yolk sacs attached from which they gained the required nutrition.

The fry started moving freely about in about three days. I the meantime, I acquired some knowledge about the food required for the fry and the care that is needed to look after them from my friends at the Aquarist Society. I then started feeding the fry with green water filtered through a muslin cloth. I siphoned out about a quarter of the water in the tank every alternate day and replaced it with fresh water. I added a mugful of green water to the tank twice a day.

The fry grew to about 5 mm. in about two weeks. I then started feeding them with yeast tablets, which I placed in a saucer on the bottom of the tank so I could easily remove the left over food.

The fry grew fast with yeast tablets, to about 10 mm. in a month's time, and I started feeding the fry, which now resembled goldfish, with micro pellets. The fish at this stage were golden black in colour, but they changed to gold in about six weeks.

I found that the goldfish fry which were exposed to sunlight developed their colour faster. The growth of all the fry was not uniform so I had to separate the bigger fry from the smaller ones which reduced the chances of them being eaten up.

I learnt a lot and had fun watching the fry grow into healthy fish. It was a fascinating experience for me and I enjoyed it.