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Goldfish fry (newly hatched goldfish) are among the cutest and most interesting types of fry in the aquarium hobby. Goldfish can lay over a hundred eggs, and the eggs can develop into delicate babies that will grow rapidly when cared for properly.
To get a healthy batch of goldfish fry, you first must look after their eggs! If you have other types of aquatic life in your aquarium, you will need to identify which animal laid that batch of eggs. Luckily, goldfish eggs are easy to identify once you know what to look for. You will also be able to determine if the eggs are fertile or not.
Neither goldfish parent will play a role in parental care for the eggs and the fry. In fact, they will try to eat them! This means the eggs will have to be removed to a special incubation tank, away from the parents.
Goldfish Breeding
A male and female goldfish will take part in a spawning ritual, where the male goldfish will chase the behind of the female goldfish. This will occur when mating season is around or if the conditions are ideal for breeding. Fertilization occurs outside the body and involves both the male and female to produce a healthy batch of fry. An egg-carrying female will be chased till she deposits eggs along the bottom of the aquarium or on top of decorations. The male goldfish will then fertilize the eggs with milt (fish sperm).
Goldfish do not stick together after mating and will part ways. This allows both goldfish to mate with other goldfish in the tank. As soon as the eggs are laid, the parents will attempt to eat them. It is therefore important to gently remove any sort of egg material from the tank with the same conditions and water and put it into a small incubation tank.
Expectant Female Goldfish
Your female goldfish will have an abnormally large belly that flattens toward the middle. She will also have the sides of their stomach stick out on either side of her body when viewed from above. In some cases, you may also see outlines of the eggs through the stretched abdomen. The female will also appear restless and less active than usual.
If you're new to the world of goldfish keeping or are experienced but love to learn more, we highly recommend you check out the best-selling book, The Truth About Goldfish, on Amazon. From diagnosing illnesses and providing correct treatments to proper nutrition, tank maintenance and water quality advice, this book will help you to ensure your goldfish are happy and to be the best goldfish keeper you can be.
Identifying a Goldfish Egg
Goldfish eggs do look like a variety of fish and invertebrates. An easy way to determine what laid the batch of eggs inside the tank is to know all the different types of aquarium life in your tank. If you have a goldfish-only tank, it can only be goldfish eggs. If you have snails or other suitable tank mates, you will find out what their respective eggs look like.
Goldfish eggs look like white to yellow or orange bubbles. These small delicate dots will usually get stuck on the substrate and leaves inside the tank. Goldfish eggs are incredibly sticky and may be hard to remove. They will also be plentiful, as a female can lay over 300 eggs, depending on her age, size, and health.
Since the eggs will be hard to remove, you want to add a spawning mop or a variety of live plants for the goldfish eggs to attach themselves to. The more hidden they are, the less likely the parents will be able to find and eat them.
How to Hatch Goldfish Eggs
- Place the eggs that are attached to a spawning mop, plant, or decoration inside a hatchery/incubation tank with a filter, heater, and aeration system.
- Keep the eggs at a warm, constant temperature between 21°C and 24°C. Make sure to use a heater to keep the temperature stable. This will encourage the eggs to hatch between 3 and 5 days.
- The eggs should be aerated by an air stone, bubbler, or spray bar. The eggs require plenty of oxygenated water to hatch.
- Infertile eggs will go a pure white color, and fertile eggs will look nearly transparent. This is seen after a day or two.
- The fry will hatch after 5 days and will look like tiny dots jerking around the water in clusters.
Caring for Goldfish Eggs and Fry
Caring for the eggs and fry is simple if you meet their temperature and water requirements. They should have constant access to clean and oxygenated water. The eggs can stay inside the hatchery until they are large enough not to be eaten by the adults. They should be twice the size of their parents’ mouths. Remove any unfertilized eggs by using a mixture of methylene blue and dechlorinated water to get rid of the fungus the infertile eggs will develop into.
Raise the fry on newly hatched baby brine shrimp and fry food from your local fish store. The fry should take a few weeks before they start to resemble their parents. At this stage, you will be able to tell what color they will be and distinguish their features. Sex will only be revealed later in their growing phase. So, if you do not wish to have any more goldfish fry on your hands, you do not need to split the fry up according to sex.
Final Thoughts
If you plan to regularly breed your goldfish, you should get used to the identification and raising process. If you have found eggs at the bottom of the aquarium and you have a round female with a male chasing her, it is more than likely a batch of goldfish eggs. Females can lay eggs without a male, but the eggs that they deposit will be infertile. Also, it is not uncommon to witness two male goldfish chasing each other for dominance over a female in the tank, so it is best to not confuse the two.
We hope that this article has helped you successfully identify and raise a healthy cluster of fry.
Featured Image Credit: stockt0_0, Shutterstock
