I think you’ll agree with me when I say:
“Goldfish are so awesome.”
And if you didn’t know how many eggs a goldfish can lay before…
… it will blow your mind!
I guarantee you’ll have a new respect for your female fishy friend after reading this!
Table of contents
A Bit About Goldfish Eggs (and How to Take Care of them)
So, exactly what do goldfish eggs look like?
Healthy goldfish eggs look like small, clear bubbles and can range in color from white to yellow-orange.
Here are what about 125 freshly-laid goldfish eggs look like:
They are also EXTREMELY sticky.
Of course, this is part of their survival strategy.
By clinging to the plants as they would fall to the bottom, they have a better chance of not being devoured.
That’s why breeders put “spawning mops” in their tanks. Usually these are made of yarn and the eggs stick to them instead.
If you want to tell if the eggs are fertilized, you can look for tiny black specks in the eggs after the two or three days or so.
Those are the eyes of the tiny fry developing inside.
This is a 3 day old (fertilized) goldfish egg:
(Isn’t that the cutest thing you’ve ever seen?!)
And a sibling… (who kind of looks like a frog)…
How long does it take for them to hatch?
In 4 to 7 days, the eggs hatch (depending on the temperature).
That is – unless fungus has taken over and killed them before they had a chance.
Fighting Fish Egg Fungus
Fungus will grow on unfertilized eggs.
It can also spread and infect the fertilized ones.
A 2-day-old goldfish egg attacked with fungus under a microscope:
There are some things to do about this.
Some people add a medication that turns the water blue to prevent fungus from taking hold…
But personally, I wouldn’t do that.
Some find a higher rate of defects in fry from eggs that have been soaked in methylene blue.
I have found when it comes to fungus, nothing is as good as MinnFinn.
The active ingredient (peracetic acid) is used in catfish hatcheries to stop the fungus from ruining the eggs – in a safer, more natural way than harsh chemical treatments.
I treat my eggs with regular strength 1 hour long bath.
Doing this 1-2x every day is a good idea.
As far as other methods go:
You can add shrimp to the tank (cherry shrimp, ghost shrimp or others).
They know how to pick out the bad eggs and eat them – but they don’t mess with the good ones.
Think of them as nature’s babysitters.
Ramshorn snails are also excellent fungus-eating egg companions.
No issues mixing them with MinnFinn treatments either.
The condition of the water is REALLY important when it comes to successfully hatching them.
Clean water with plenty of aeration will help to prevent fungus, as well as removing infertile eggs right away (which will spread the fungus).
Water changes 1-2x per day is usually a good idea.
If you don’t have live plants in the water, a small sponge filter is a good idea.
Here’s a 1-day old newly hatched fry:
They spend a couple of days hanging out on the sides of the tank…
… And occasionally, trying to learn how to swim.
They feed off of their egg sack until they are ready for their first meal in another 2 days – no point in feeding them before then.
When the eggs hatch, if there are more than 300 you probably need to perform a water change as the contents can foul the water.
The tiny little wriggling creatures that emerge look like some kind of strange insect.
They start looking a little more like actual goldfish as they get older, usually in several weeks to a couple of months.
The hungry fry will demand a lot of food as they grow!
Once full-grown, it all starts over again.
Read More: Raising Baby Goldfish Fry
Just How Does a Goldfish Lay Eggs (And How Many)?
Let’s set the record straight:
A female goldfish can never be pregnant. (Read why here.)
But she can swell up with the eggs, and even perish from a condition called egg-binding if things get complicated and a male doesn’t spawn with her.
So yes, goldfish do lay eggs – and they can lay a whole bunch of them.
How many babies she will have depends on her age and how much she’s been eating…
But a goldfish can easily lay over 1,000 eggs at one time!
That’s just at one time.
During breeding season, goldfish will often spawn multiple times on a weekly basis.
Talk about a family reunion!
So if you miss out on the first spawning and the parents gobble up the unhatched youngsters before you can interfere, don’t feel too bummed – keep a close eye on them for the next week.
Here’s a tip: goldfish usually spawn early in the morning. If you wake up before sunrise, you should be just in time for the show and should be able to separate out any eggs before they get eaten.
(Landing on something removable like plants or a spawning mop really helps.)
Like chickens, a female goldfish actually CAN lay eggs without spawning with a male goldfish.
They won’t hatch though.
These infertile eggs usually get eaten up or decompose in the water.
If she’s ready to spawn, she’ll start releasing pheromones into the water that let the males know it’s time to breed.
They will then chase the female around, nudging her sides until the eggs come out.
As they fall through the water, he’ll fertilize them with his milt.
Read More: How to Breed Goldfish
Goldfish make HORRIBLE parents.
They will eat all of their eggs faster than you can dial up Child Protection Services…
… And they will even eat their own newly hatched fry.
Any other bystander goldfish around will happily join in the cannibalistic buffet.
So if you want to make sure your eggs hatch, they will need to be separated as soon as possible.
What Do You Think?
I hope you were amazed by what you learned.
Now I’m turning it over to you.
Have you ever tried to take care of goldfish eggs, or seen any in your pond or tank?