Q&A for How to Breed Goldfish

Generally, 1 inch of fish per two gallons of water is a good rule of thumb.

Lower the aquarium temperature to 52 degrees, then when you are ready to breed them, raise the temperature 3 degrees per day until it reaches 72 degrees.

Goldfish eggs look like tiny, gooey beads that are clumped together. They can be pale yellow, white, or grey in color. Some may also have have dark specks inside of them. These specks are the baby goldfish.

The male will push the female into the plants (or spawning mobs) and help her to lay the eggs on the plants while the male the eggs fertilizes.

They will have red dotted centers.

The reasons they are chasing this one fish may be because the one fish could be the only female, and is sending off a hormonal sent which is causing all the chasing. The way to handle this would be to just remove the one fish from the tank that all the others are in and put it in a separate tank, perhaps with a new fish friend who is more docile.

It will take about 3 days in time to 7 days, depending upon the temperature of the water.

Examine the vent of the fish. This is just below the caudal fin (tail). If it is convex, or bulging, then it is a female. A concave vent is indicative of a male. Males also tend to be slightly smaller than females.

Check the color of your goldfish. If it has a greenish bronze coloration, it's probably under the age of one. If it has a gold metallic coloration, it is probably an adult (two to 25 years old). You may find it helpful to read How to Tell if Your Goldfish Is an Adult .

Yes, goldfish may lay eggs in a glass tank.

As many as 1,000 or more eggs.

You should put the female in the tank first because the male will naturally come find the female when he is ready to breed.

Yes, but if they are all chasing one female at the same time, she might get hurt.

No, he will not. He will just eat them. That is why you also need to separate the female from the eggs as well. Both the fish will eat the eggs.

You can tell because the eggs will float around and there will be little black dots around the breeding tank.

70-75 degrees Fahrenheit is best.

Your fish will breed in spring time when the water warms up. Make sure you have both males and females.

The female may not be interested in the male or is just not yet ready to mate.

Your goldfish may not be fertile, or female at all. Some male goldfish don't develop breeding stars; it's usually a genetic disorder, but it isn't uncommon.

This could be a sign of too much ammonia. Change at least 90% of the water immediately.

Once every 3 months.

It mostly depends on the species of goldfish. When females are pregnant, though, they tend to be larger than males.

No. However, the reason that she is acting this way is because she has had a long and stressful labor. She may refuse to eat at first but she should start if you give her treats like blood worms and/or shrimp.

You can't because they are different species and won't breed.

Yes, they could, but only in a pond. This is because, in an outdoor pond, the seasonal climate changes will happen and the fish will find insects and things inside the pond anyway. If a tank indoors is not given temperature and dietary changes, the fish won’t breed. It’s also worth noting that if the fish breed naturally in a pond without human help, only a few fish will survive, due to their parents having a snack on their own fry.

Yes. Goldfish are carnivores and will eat anything that fits into their mouths, including their young.

Fish eggs are protected by a jelly like coat so they squish and don't crack.

Wait until you know that the eggs have been fertilized, then follow the steps above.

Yes, because they are both the same species.

It could. However, they may simply be schooling together for company or safety. If the male follows the female, it may be something more. If the female follows the male, it's probably for company.