Baby Goldfish: How to take care of goldfish babies

Caring for goldfish can be very rewarding. You set up their tank, make sure their water is just right , choose what food they eat, and watch your goldfish grow and play.

But there is something even more rewarding than looking after a goldfish you bought from the pet store. How about raising a goldfish all the way from birth to adulthood?

In this guide to baby goldfish, we look at how goldfish babies are born, how they grow, and – most importantly – how you should care for them.

How do goldfish have babies?

Before baby goldfish can be born, two sexually mature adult male and female goldfish must mate.

Goldfish only mate at specific times and under specific conditions. For example, the temperature of the tank is important.

If you’re not sure how to encourage your goldfish to mate, or if they are ready, check out our guide to breeding goldfish to learn more.

Once your goldfish have successfully mated, the female goldfish will lay eggs. Then, the male goldfish will fertilize the eggs.

Goldfish eggs in a tank. These eggs are two days old.

About 4 days later, the eggs that were successfully fertilized and survive – i.e. don’t get eaten by the adult goldfish or sucked into your filter! – will hatch.

Your goldfish babies have been born!

What do the babies look like?

Once your goldfish eggs hatch, you’ll need to look closely to find the tiny goldfish babies.

For the first 4 days or so they will be stuck to the leaves of your plants, so look carefully. Where you previously just saw eggs, you should now see tiny black baby goldfish with their yolk sacs attached.

After about 3 more days, your goldfish will be able to swim around freely.

What color are the babies and how does this change?

Newborn baby goldfish start out black.

As they grow, they develop a brown color, perhaps with hints of silver. Some areas of their body are almost see-through.

It can take up to two years for a goldfish to fully develop its color.

And even then, goldfish can continue to change color throughout their lives.

Baby goldfish growth rate

Of course, baby goldfish don’t stay so tiny and black in color for long.

One of the joys of breeding goldfish is that you get to see the babies grow and develop over time.

Once your baby goldfish reach the free-swimming stage, their bodies will be around 5mm long. They will have a very small stubby tail, pectoral fins (on their sides) and a fin on their back too.

A very young goldfish fry

Over the next week, your baby goldfish will grow by almost 40%. Their caudal fin (the tail fin) will develop a lot during this stage of growth.

This video shows two-week old goldfish flapping their tail fins in the water.

The following week – the third week after hatching – your goldfish will continue to grow quickly. You’ll also notice their dorsal fin (the fin on their back) becoming more defined.

At three weeks old, the dorsal fin is clearly visible from some angles.

By the fourth week, the dorsal fin will be well developed.

By the fifth week, all of your fish’s fins will be well developed and they will have scales.

From week six onward, your fish is essentially “complete”. Like a miniature version of an adult goldfish. From now on, it’s all about growing in size and weight.

Caring for baby goldfish

Tank

To stop your adult fish from eating their own eggs, you should remove your goldfish eggs from your main tank as soon as they have been fertilized by the male.

Removing the eggs could be as simple as transferring your spawning mop, if you used one. Or you may have to gently siphon the eggs off things like plants and decorations.

Place the eggs into a small tank – perhaps 3 to 5 gallons in size – with around six inches of water.

Add a small sponge filter to the tank. Don’t add a large, powerful box filter, as the babies will very likely get sucked inside!

Your baby goldfish should stay in smaller tanks – separate to the adult fish – until they meet two important conditions:

  1. They are strong enough swimmers to not get sucked into the main tank’s filter
  2. They are bigger than the adult fish’s mouths!

Only once these conditions are met should you add babies to an adult tank.

Temperature

We recommend maintaining a temperature between 70-75oF (21-24oC) in your baby goldfish tank. This temperature is warm enough to encourage rapid growth, but without being too hot for your fish.

It’s very important to avoid any sudden changes in temperature. A sudden drop to a cold temperature will stress your fish, which could cause them to get sick or even die.

Food

The first few days

For the few first days after hatching, you should not feed your baby goldfish at all.

While this might seem odd, it’s because the goldfish arrive well-prepared with their own packed lunchbox!

Baby goldfish hatch with a “yolk sac” attached to their bodies. This pouch contains all the food they need for the first few days.

The first month

Take some hard-boiled egg yolk and soak it in water. Give it a good shake, then add to your baby goldfish tank in small quantities.

You may also wish to try crushed brine shrimp and baby fish food.

Remove any food that is left uneaten so that it doesn’t pollute your tank.

The second month on

Your fish should now be able to eat the same foods you feed to your adult goldfish.

Just be sure to crush up the food if necessary. You need to make sure the pieces aren’t too big for the babies mouths!

Death

We should add that – no matter how well you care for the babies – you should be prepared for lots of them to die.

The reason that goldfish lay so many eggs, and that so many babies hatch, is that only a small percentage make it to adulthood. They need to have lots of babies to ensure that some survive.

If you manage to keep 20% or more of your baby goldfish alive to give away to other people, or to move to your adult tank, you’ve done very well.

What are baby goldfish called?

Throughout this article, we’ve referred to the little new members of your goldfish family as “babies”. However, this isn’t the technical term for baby goldfish.

When they first hatch from their eggs, baby goldfish are called larvae. They carry a yolk sac with them for food. This periods lasts for two to three days.

The baby goldfish then lose their yolk sacs and become capable of feeding themselves. Once they reach this stage, the babies are called Fry.

Once baby goldfish develop scales and have fully formed fins, they are known as juveniles. This phase lasts until the goldfish is a sexually mature adult fish.

17 thoughts on “Baby Goldfish: How to take care of goldfish babies”

  1. Thank you very much for good information about gold fish my fish lays eggs and produces many babies but now in two weeks they have become very few there for I want all beginners information so I could help the remaining babies

    Reply
  2. My goldfish had babies without me knowing it! 2 have survived in the pond with the others to a size that I think they are safe from being eaten!

    Reply
    • I had just three goldfish left in my 10 foot pond after attacks by cats and herons. Then one day I saw a tiny silvery thing slithering about near the top of the pond lining. I wonder if it was some sort of baby newt. Eventually I began to see about 40 tadpole shapes swimming around and then I figured my fish must have bred. I began feeding them and they use to come up to the surface, without fear, when they knew I was there. They have survived a harsh winter here in the UK, sometimes being under the ice for 2 days. I have possibly 30 left now. I wish I could get live food for them but nowhere seems to sell it. The fish are a joy to keep.

      Reply
  3. Thanks for the info. Our goldfish have previously eaten all their babies and I found some tiddlers this year and have put them into a bowl of the pondwater with some weed. They are under 1/2 inch (about 10cm ) long. I hope I can keep them alive long enough to return them.

    Reply
  4. Great information.
    We have feeder fish for our turtles. The turtles are lazy and eat the food instead.
    One of the fish laid a hatch. now we have about 150 small goldfish about 1/2 – 3/4 inches long. We have them in a small 5 gallon tank. I will put foam around the filter as some are getting stuck to the intake.
    What kind of room do they require? I seen to remember 1 gallon per inch. But I would have to get rid of my turtles to put them in a 120 gallon tank.
    Any ideas?

    Reply
    • If you keep feeding your turtles they aren’t going to eat the fish or they may be vegetarian, not all turtles eat fish.

      Reply
  5. Hello! My goldfish (Oranda and Black Moor) had babies last month, I managed to move 6 into another tank to protect them. It’s almost a month now but they are still tiny. I thought they’d be a bit bigger by now. Am I doing something wrong? All six are still alive and swimming around but so tiny… nothing like this pics on this page. Any advice? I was going to give them to the petshop when they were a bit older, I’m not looking to keep any or keep breeding – will let nature takes it’s course going forward. Thank you!

    Reply
    • Hi Emily, thanks for your comment,
      fish will grow at different rates depending on different factors, the main two are water temperature and amount of food.

      To raise fish quickly, breeders will sometimes feed fry 5 times a day, perform 2 water changes a day, and keep the water temp up to 27C!

      Of course this isn’t required, as long as your fish are healthy and growing at a steady rate, it can take as long they need, there is no rush to grow your goldfish up to a standard , even individuals will grow at different rates, much like us humans.
      hope this helps

      Reply
  6. Thanks for advice and information, my goldfish spawned around two weeks ago. I’ve just noticed quite a few swimmers around 2-3mm and have put them in a floating bowl attached to a shady side of our ponds structure. 1st year in having a garden pond and amazed they’ve settled and doing their thing just 8months since getting them and setting up.
    I wasn’t sure if I was doing the right thing or what to feed them, your advice has eased my mind cheers and regards. D

    Reply
  7. I have 2 ponds, last year my goldfish bred and about 8 babies survived. I didn’t remove them or interfere in any way as I didn’t really want anymore fish. They all survived the winter, and I gave 4 away. We have a particularly pretty white, gold, orange and black one. My fish are currently breeding again. I live in the south of England.

    Reply
  8. Hello in very excited to have loads of baby goldfish and swimming strong, unfortunately now the water has gone cloudy and I don’t know what to do I don’t want to stress them out ..can someone please let me know what to do to fix this so they have clean water , they are only 1 day old

    Reply
    • Hi Jenny, we are glad to hear you have managed to breed your goldfish!

      Taking care of fry can be very high maintenance, for the first week, we recommend feeding 2 – 3 times a day and performing water changes once everyday.

      Don’t worry, your baby goldfish will be fine with this, and it is very important for them to have clean water.

      if you are worried about accidentally sucking up any goldfish while doing a change, wrap some stocking over a syphon to stop them from being pulled in.

      hope this helps, and good luck with your new babies

      Reply
  9. My Orando male goldfish mated with my Female Pearlscale. Will the babies survive? What will their weaknesses be? And will they need special care?

    Reply
    • Hi Jaycee,

      I personally haven’t crossed these two breeds before, but I imagine they should survive just fine.

      They may get issues with their swimming and feeding capabilities, due to them having both the wen and the ballooned body, but as long as you make sure they are eating, and don’t house them with fish which can out compete them, they should be fine.

      good luck with the babies.

      Reply
  10. Hi. I’ve noticed a beautiful baby, black and gold fish about 15mm in my pond. I have a large white goldfish. A black and gold fan tail and a standard gold fish. Do you think the others will eat it? I’m really don’t want to lose it! I’ve notice black
    Babies before but none have survived to grow up. I’ve a huge deep pond with plants and lots of hiding places and shelves so really want more fish lol

    Reply

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