How to tell if a goldfish is pregnant

Finding out if your goldfish is pregnant isn’t as simple as you may think. Similarly to humans, goldfish can get bloated easily if something doesn’t agree with their digestive system so we can’t jump to any conclusions. If you have a range of male and female goldfish in your aquarium, you need to be prepared for the unexpected. In the wild, goldfish go through seasons as to when they need to spawn. This is usually in spring or early summer. However, pet fish could spawn at any given time. 

Could your goldfish be pregnant? We’re here to help you out! We are going to outline the top signs that you need to look out for when you’re asking yourself this question. 

First up, you’ll need to figure out if your goldfish is a she. You can usually tell if a goldfish is a female by looking at the shape of the fish from above. If the goldfish is more round below its fins and before its tail, it is more than likely to be a female. The fact that female goldfish are usually curvier than male goldfish does make it even more difficult to determine whether your fish is preparing to spawn.

One common way to tell if your goldfish is looking to spawn is by observing the male’s behavior in the tank. The males love to grab the female’s attention by chasing them around the aquarium. This may come out of nowhere and if your fish are usually laid back, it is quite easy to sense that your fish are feeling frisky. 

Another good way to check if your goldfish is pregnant is by observing the female’s behavior in the tank. Has she become quiet and isn’t acting quite like herself? Wouldn’t it be so much easier if we could just simply ask her what’s wrong! As that is never going to happen, check to see if her activity level has reduced. Does she seem to be hanging around at the lower part of the tank more often? If she is laying lower in the aquarium, she is probably getting ready to nest. 

Nesting is how your goldfish will lay her eggs. Usually, your goldfish will scout out a quiet corner in the aquarium to begin spawning. Usually somewhere covered or hidden out of sight works best for them to lay their eggs safely. Don’t panic if she spends most of her time hiding out of sight as she is just getting ready to become a mom. 

You may notice at some point that your female fish is refusing to eat any food. Don’t worry, she isn’t sick. She is just coming to the end of her pregnancy and getting ready to lay her eggs in her nesting area. Just keep adding food to your aquarium as usual and let her do her thing! She will snack when she’s hungry but right now, her body is going through some changes. 

Your goldfish has now found a nesting area, is looking quite large, and is out of sight for the majority of the time. Ladies and gents, it could be time. Your goldfish is ready to lay her eggs. At this moment in time, she will release pheromones to let the male goldfish know that she is ready. The male goldfish will then swim up to her and bump the sides of her to start nudging the eggs out. The eggs will then drop to the bottom of the tank and stick to where they have fallen. 

This will usually take place early in the morning and your goldfish could lay up to a thousand eggs, depending on her age. However, don’t expect one thousand babies to be swimming around in your tank! Newsflash, goldfish are savage. Once they have laid their eggs, they will end up eating the majority of them. They do this because the eggs are rich in protein and nutrients.

If you want to stop the female from eating her eggs, it is a good idea to separate her into a different tank. You don’t have to feel guilty about doing this at all. The goldfish actually have zero maternal instincts. Nada! In fact, when the eggs hatch and the new additions to the tank are still quite small, the female goldfish will still be tempted to eat them. We told you they were savage!

Another thing to bear in mind is that females will lay eggs even if there isn’t a male present. When it is spawning season, your goldfish will lay eggs multiple times a week. Whether they will be fertilized is another story. If they aren’t fertilized, the female will either eat the eggs or they will decay with time. 

If there are male goldfish present, then some eggs will be fertilized. Once the eggs reach the bottom of the tank, the male will come along and fertilize them with his milt. Then the eggs will hatch in two to seven days. You can tell if the egg has been fertilized by checking to see if there is a black dot inside them. Otherwise, the egg will just look clear.

It can be very difficult to spot your new additions to your tank as they will be so small. Baby goldfish will also start off their lives by almost looking transparent. If you want to see them, look in between the stones at the bottom of your aquarium. If you look closely enough, you may see some tiny fish moving through the water. 

Baby goldfish will lay low until they have developed fully as they will be prey for the larger fish in the tank at first. They will also be quite delicate when they are born so they like to hide away in between the stones at the bottom of the tank, plants, or decorations placed in the aquarium. This protects them from any harm or danger they may face.

So, is your goldfish pregnant? Is she laying low, hiding away, and looking extremely large? These are all great indicators that you could be a goldfish grandparent. We hope we’ve helped you clear some things up and good luck with your new additions!