How long do fish eggs take to hatch?

In this brief guide, we will answer ‘how long do fish eggs take to hatch?’ Also, we will look into some ways you can facilitate the process and some frequently asked questions are also answered here.

How long do fish eggs take to hatch?

Fish eggs may take up to 3 – 7 days depending upon species, tank condition and water temperature. 

After fertilization, hatching will take no longer than 7 days if the water temperature is warm and stable. But if it is not, it may take up to ten days.

Following is the list of common aquarium species and the duration their eggs take to hatch;

Bettas2 – 3 days
Discus3 – 4 days
Goldfish2 – 7 days
Cory catfish3 – 6 days
Angelfish4 – 7 days
Tetras2 – 5 days
Bristlenose pleco4 – 10 days
Danios1 – 2 days
Gourami2 – 4 days

Can you breed fish in an aquarium?

Yes, you can. If you have noticed that your pets have laid some eggs or you want to experiment and experience the process thoroughly, you may need a male fish, a female and a suitable breeding environment depending upon your choice of species.  

Mentioned below is the most important factor that you need to keep in mind when breeding fish.

Time of spawning

Most freshwater species require warmer weather for spawning that occurs from April to early June. But at home, aquariums come with a stable and constant environment to keep your fish, so spawning can be carried throughout the year.

Common aquarium species like angelfish or goldfish only require suitable water conditions to spawn.

What to do after fish eggs are laid?

It is best to separate the eggs in a different tank, so as to protect the eggs from other fishes. Also, the females sometimes end up eating their own eggs so it’s best to move the eggs to a different tank.

Most fishes need a hard surface to lay their eggs, like the tank wall or any decoration available. So be careful when moving.

Females can lay up to hundreds or thousands of eggs in a single spawning but it is not necessary that all the eggs will get fertilized by the males. It is  best to have more males so that there is a greater chance of successful fertilization.

How to tell if the fish eggs are not fertilized?

If the eggs remain opaque, white after 2 – 3 days, spawning was unsuccessful meaning the eggs are not fertilized or there’s no male. Sometimes bacteria can also attack the eggs resulting in white eggs.

Fish eggs range within a light brown color depending on species and small eyes become visible soon after fertilization.

In some cases, the eggs might be too close together that there might not be enough oxygen for all the eggs, making the eggs go white because of the fungus. But if you notice fertilized eggs around them, it’s best to let them be and have a fair chance at hatching.

Frequently asked questions

Let’s look into some common questions any new breeder has and how you may tackle those.

How to take care of eggs in an aquarium?

Different species have different requirements which you need to plan out in advance if you are intentionally breeding.

Like some fishes lay their eggs on hidden surfaces and some on hard surfaces while some need a cave or isolated place. Some use plants, some may bury their eggs till it’s time for them to hatch while some lay in a nest of bubbles. So make sure your aquarium is well equipped with those.

Second, make sure the environment you are providing is according to their own specific needs.

Thirdly, make sure that the water is clean to minimize the occurrence of any fungal or bacterial infections that may compromise your eggs.

How to stop eggs from being eaten?

Simply separate them after they are spawned. To make it simple, move the parents and not eggs as it will disrupt their hatching. 

If you want to read more on fish hatching please visit here or here.

Other FAQs about Eggs that you may be interested in.

How Long Are Eggs Good For If Left Out

Can you eat peacock eggs?

Can you eat pasteurized eggs raw?


In this brief guide, we answered ‘how long do fish eggs take to hatch?’ Also, we have looked into some ways to facilitate the process and some frequently asked questions are also covered here.

Hopefully, you found this guide helpful. If you have any questions or comments please let us know.