Skip to Content

Oscar Fish Breeding Guide (Answers to Common Questions)

Oscar Fish Breeding Guide (Answers to Common Questions)

Share this post:

This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addition, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Have you recently purchased oscar fish for your tank? Many people fall in love with these fish because they make such great pets.

People enjoy oscars because they’re so full of personality. Many compare them to dogs because they can be that much fun once you get used to caring for them.

They’re hardy fish that can live for a long time. You might even want more of them for your fish tanks.

One good way to get more fish is to allow your male and female oscar fish pair to breed. What do you need to know about breeding these fish?

Continue reading to learn everything that you must know about oscar fish breeding. This will ensure that you have a smooth experience even as a relative novice.

How to Breed Oscar Fish

Breeding oscar fish is going to be a multi-step process. To get started, you must acquire some oscar fish.

Buy at least one breeding pair of oscars to get started. Note that it isn’t always simple to tell oscar fish apart based on sex.

Oscar fish pretty much look the same whether they’re male or female. So you have to look at the sex organs to tell which is which.

Buy oscars from a reputable store where knowledgeable clerks can ensure that you get one male and one female oscar fish. This will make things easier.

Of course, you can only tell whether the oscars are male or female if they’re adult fish. Juveniles haven’t grown enough to be able to distinguish which sex they are.

In the future, you should know that you can tell oscar fish apart by looking at the sex organs. Both males and females have two holes near the anal area.

A male will have a sex organ that looks like a thin spike. Females have a much wider and blunt sex organ.

This is because that is the tube where the eggs come out. You could describe the female sex organ as short and flat.

Venting fish can be somewhat dangerous when you don’t know what you’re doing because you don’t want to harm the fish. However, this is the only reliable way to tell if a fish is male or female.

Ask for help if you need to vent the fish to determine the sex. You can get assistance from a vet for exotic animals or an experienced fish tank enthusiast in your area (assuming that you know someone).

Once you know that you have a male and female in your tank, you must wait for them to form a breeding pair. Fish might not be interested in breeding until they are a few years old.

In some cases, the fish might not form a breeding pair until they are three years old. You must be patient.

You Could Buy a Proven Breeding Pair

Pair of Tiger Oscars Swimming in a Tank

Buying a proven breeding pair at a pet store might be your best bet. This will allow you to get fish that have already formed a pair.

Sometimes pet stores will sell breeding pairs that have successfully bred in the past. You can always ask local pet stores to see if they have what you’re looking for.

If they don’t, you can choose to look elsewhere. Otherwise, you might simply want to acquire oscars and wait for them to grow to be the right age.

Do your best to get a male and a female oscar fish. If you want to breed the fish right now, buying a breeding pair is sensible.

Provide Optimal Conditions

Providing optimal conditions for the fish will coax them to breed. You want to put the oscars in an aquarium that is the right size.

If the oscars are close to full size, it’s best to have them in a 100-gallon fish tank. If the two oscars are smaller, you can get away with a slightly smaller tank.

Just know that it’s best to keep the oscars in a large tank to encourage maximum growth. Ensure that the fish tank has a powerful filter that will help to keep things clean.

The temperature of the water must stay between 74 degrees Fahrenheit and 81 degrees Fahrenheit. The best temperature is said to be 77 degrees Fahrenheit.

Monitor the pH balance of the water carefully. It’s supposed to stay between 6.0 and 8.0 with the best pH balance number being 7.2.

To trigger spawning, you should raise the temperature of the water slightly. When the fish show signs of forming a breeding pair, raise the temperature to 82 degrees Fahrenheit.

You’ll need a large and powerful aquarium heater to get the job done. You should also do more regular water changes.

Start changing 25 to 50% of the water each week. This should encourage the fish to breed further.

Feed the Oscars Properly

Oscar Fish Eating a Frog

Feeding the oscars properly is a part of getting them to breed. You can continue to feed oscars cichlid flakes and nutritional pellets each day.

Supplement the diet of these fish with live foods. Consider feeding the fish shrimp, worms, and invertebrates.

It’s also acceptable to feed these fish frozen food or freeze-dried food. Some people find this to be more convenient than feeding fish live food.

You can easily buy what you need from local pet stores. Ensuring that the oscars get the nutrients that they need to thrive will make it more likely that they can produce viable eggs.

Some of the best options to feed your oscars include brine shrimp, mealworms, crickets, beef hearts, and ocean plankton. You can give them invertebrates such as aquarium snails as well if you’re so inclined.

What Happens When Oscars Get Ready to Mate?

When oscar fish are getting ready to mate, you’ll see them start acting differently. It’s common to see the two fish flare their gills.

They do all sorts of actions toward each other. Shaking is a very common action that is associated with breeding.

So is fin-spreading and wagging. You might even notice the two fish lock jaws and shake each other a bit.

Eventually, the female fish is going to start clearing the area near the rocks. Oscars like to lay eggs on flat rocks.

You should place a flat rock that is dark in color in the tank. This will be the perfect type of rock for oscars to use as an egg-laying surface.

The fish will clean the rock for quite some time. In some cases, this cleaning will go on for many days or even longer than a week.

Eventually, you’ll see that the female’s ovipositor will descend from its body. This means that the female is ready to lay its eggs.

The female oscar fish will lay the eggs on the surface of a flat rock. Then the male will use its breeding tube to spray the eggs as it passes over them.

You should expect the spawning process to take several hours. Typically, it takes around three hours to finish up.

Do Oscar Fish Lay Eggs?

Yes, oscar fish do indeed lay eggs. Female oscar fish lay eggs on the flat surface of rocks. It’s best to have a flat rock that is dark in color in the tank.

This makes it a lot easier to see the eggs against the rock. You should ensure that you put the right type of rock in the tank or your fish might not breed properly.

Once the eggs have been laid, the parent fish will guard them. It will take two or three days for the eggs to hatch.

How Often Do Oscars Lay Eggs?

Oscar Fish Near Bottom of Tank

It’s possible for oscars to lay eggs every month. However, they might not always lay eggs this often.

Most sources say that oscars can lay eggs every 22 to 45 days. However, it’ll sometimes be a few months between spawning sessions.

You can expect a breeding pair of oscars to lay eggs at least four or five times per year. This is assuming that you’re providing optimal conditions.

How Many Eggs Do Oscars Lay At Once?

Oscars have the potential to lay so many eggs at once. The larger the fish, the more eggs will be laid at once.

A six-inch oscar fish that still has some growing to do might lay 300 to 500 eggs at once. A fully-grown oscar fish that is twelve inches long has the potential to lay up to 3,000 eggs.

There will be a large number of eggs even if your oscars are not fully-grown. You’ll have either hundreds of eggs or thousands of eggs to deal with.

What Do Oscar Fish Eggs Look Like?

Oscar fish eggs have a white appearance when they are first laid. They’re going to be around one millimeter in diameter.

After a day or so, the appearance of the egg will change. It’ll look darker, similar to a little ball of chocolate.

When the eggs get fertilized by a male oscar fish, they go from being white to taking on a tan color. Only unfertilized eggs will remain white.

Eventually, unfertilized eggs will start to develop fungal growth. It’s common for some of the eggs to be missed by the male during the fertilization process.

Since female oscars lay hundreds (or potentially thousands) of eggs, it makes sense that not every single egg would get fertilized. Many describe the look of the eggs to be salt-like when they’re laid on a dark-colored rock.

Oscar Fish Breeding Signs

There are several different breeding signs that you can look out for. It’s normal to see oscars start chasing each other in the tank when they’re forming a breeding pair.

They will frequently swim together and chase each other around the fish tank. You might see the oscars lock lips and shake each other, too.

Shaking and tail lashing are considered to be standard breeding signs for these fish. When you see the fish acting this way, it’s an indication that they might breed soon.

You can try to make subtle changes in the tank to encourage the fish to breed. As mentioned earlier, this involves raising the temperature in the fish tank and ensuring that you feed the fish properly.

How Do Oscar Fish Mate?

Two Oscar Fish Facing Each Other

Oscar fish mate much in the same way that other fish do. There are breeding signs and mating rituals that they go through.

The two fish will chase each other around in the tank. It’s common for the fish to lock jaws and shake each other.

Eventually, the female oscar is going to start meticulously cleaning the surface of a flat rock. The male will help with this.

The process of cleaning the rock might take several days. Sometimes the fish might keep doing this for over a week.

When the time is right, the female fish will lay eggs on the surface of the flat rock. The male oscar fish will then pass over the eggs to fertilize them.

After two or three days, the eggs will hatch. This is the basic process that you can expect when attempting to breed oscars in your fish tank.

Can Oscars Lay Eggs Without a Male?

Female oscars can lay eggs whether a male is present or not. It doesn’t matter whether a male is there to fertilize the eggs.

You could have two female oscar fish in the tank and wind up seeing one of them lay eggs. At some point, both females should lay eggs.

The eggs won’t be viable and the fish in the tank will just wind up eating them. Males are necessary when you want the eggs to hatch and produce babies.

Female fish don’t rely on male fish to be able to lay eggs. They can lay eggs naturally, but the male fish have the necessary biological tools to fertilize the eggs and make them viable.

How Old Do Oscars Have to Be to Breed?

Oscar fish have to reach a certain maturity level to be able to breed. Some people say that they will be able to breed once they reach five inches or so in size.

This isn’t completely accurate. It’s going to take time for fish to reach the right maturity level and develop the ability to breed.

Expect oscar fish to be ready to breed once they are fourteen months old. Some fish might be ready a bit sooner and will be capable of breeding once they are twelve months old.

Using the size of the fish to determine its age isn’t wise. How fast a fish grows depends on many factors such as what the fish is being fed and whether it’s being cared for in ideal conditions.

Simply wait until the fish is for sure old enough to breed. Then you can worry about determining the sex of the fish and attempting to coax the fish to form breeding pairs.

Oscar Fish Breeding Tank Setup

An Oscar Fish in a Tank

Setting up an oscar fish breeding tank is simple enough. You just want to have a tank that is large enough for the two oscars to be comfortable.

Many enthusiasts say that a 100-gallon fish tank will be perfect for this. oscars can grow to be quite large and you want the breeding pair to be comfortable so they will want to breed.

It’s also imperative to have a powerful heater in the tank. You need to heat the tank to around 83 degrees Fahrenheit to coax the fish to breed.

In the tank, you’ll want to have flat rocks on the bottom. Flat rocks that are dark in color will be the best spots for fish to lay their eggs.

The dark color makes it easier for you to see the eggs. Continue to feed your fish well and make sure that they’re getting a varied diet.

Feed them more than just cichlid flakes and pellets. Give them live food options such as worms, shrimp, and aquarium snails.

You should be able to get these fish to want to breed in your tank. It just might take a little time and they will begin exhibiting signs that they’re going to mate.

Do Oscars Eat Their Own Eggs?

Oscars are known for eating their own eggs. This isn’t something that is unique to oscars, though.

Many types of fish are known to eat their own eggs. Sometimes parent fish will do this to help the other eggs survive.

For example, they might eat eggs that aren’t viable or ones that are starting to show signs of fungal growth. Other times, fish might eat the eggs simply because they need the energy.

If oscars become stressed, they might eat all of the eggs due to anxiety. This would be an unfortunate situation, but it can indeed happen in your fish tank if you aren’t careful.

Some people remove the parent fish from the breeding tank once the eggs have been laid and fertilized. You’d have to care for them if you choose to do this, but it might help as many fish to hatch as possible if you do things right.

Do Oscars Eat Their Babies?

Yes, it’s common for oscars to eat their babies. Oscar fish fry aren’t necessarily going to be safe from the parent fish.

You might notice the oscar fish eating the fry quite often. There will potentially be many of them in the tank due to the fact that oscars lay so many eggs at once.

This is why many people choose to separate the parent fish once the eggs have been laid. If you want to ensure that as many oscar fish fry to survive as possible, it’s likely best to care for them yourself.

Artificial Incubation Advice

So what if you want to care for the eggs yourself? You can remove the parent fish from the tank or remove the flat rock with the eggs on it from the tank.

If you remove the rock from the tank, it should be placed in a 10-gallon fish tank with appropriate water parameters. You’ll need to place an airstone near the eggs to keep things oxygenated.

It’s also recommended to add an antimicrobial agent to the water. This will darken the water a bit, but it will protect from issues with flagellates.

Continue to look after the eggs and they should hatch within three days. It doesn’t take long for them to hatch.

What to Do with the Babies

Small Oscar Fish

So what do you do with the babies once they’ve hatched? You care for them and give them food that they can eat.

At first, they will be small and will need to be fed crush-up food or small things such as freshly-hatched brine shrimp. The oscar fish fry will continue to grow and eventually will be able to eat the same food you give to your normal oscar fish.

You might wind up with more oscars than you bargained for. If you need to get rid of oscar fish, you can see if local pet stores will take them off of your hands.

Often, this will be the most convenient option. You could also give fish away to friends or family members who are interested in having oscars in their home aquariums.

Final Thoughts

You’ve learned everything that you need to know about breeding oscar fish. These fish are great to own, and breeding them won’t be that tough.

It’s easy enough to breed these fish if you provide them with ideal conditions. Keep them in a fish tank that is large enough and feed the fish properly.

Raise the temperature in the water to 83 degrees Fahrenheit, and it’ll coax the fish to breed. Female oscar fish will lay hundreds of eggs, or perhaps even lay more than a thousand.

The oscar fish might eat the eggs if you’re not careful. They’re also known to eat the fry once they hatch.

This is why many people separate the eggs from the parent fish. You can hatch the eggs yourself so as many fish survive as possible.

Enjoy your fish and do your best to care for them. Remember not to breed more oscar fish than you can handle unless you have a solid plan to get rid of them.

Share this post: