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Can Angelfish Change Gender? (And How to Tell Them Apart)

Can Angelfish Change Gender? (And How to Tell Them Apart)

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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.

If you’re loving taking care of your angelfish, then you might wish to try to learn everything that you can about them. These are common fish that many people choose to purchase for their aquariums.

However, there’s a lot that you might not know about angelfish despite them being among the most popular pet fish around. Many have trouble discerning the gender of the angelfish.

You might even be curious if angelfish are among the types of fish that are capable of changing gender. This is something that some fish are able to pull off, but can angelfish do it?

Read on to learn whether or not angelfish can change gender. You’ll also be able to learn more about how to tell angelfish apart so that you can have an easier time.

Common Angelfish Cannot Change Gender

The common angelfish that you’re most likely familiar with are not capable of changing gender. This means that popular types of angelfish such as silver angelfish, koi angelfish, marbled angelfish, zebra angelfish, and gold angelfish won’t be capable of switching from one gender to another.

However, there are some more exotic saltwater angelfish that can change gender. You just need to note that this isn’t a typical angelfish and that you’re unlikely to be keeping this fish in an aquarium setting.

Later, you’ll be able to learn more about one of the most well-known saltwater angelfish that is capable of changing gender. For now, you should know that the angelfish that you likely own aren’t capable of this feat.

Standard freshwater angelfish will either be male or female at birth. It can actually be sort of difficult to tell the males and females apart until you’ve learned to spot the differences.

Most newcomers to the hobby will have no idea how to pick out a male or a female angelfish in a group. They probably all look very similar to you overall.

Below, you’ll learn a bit more about telling angelfish apart so that you can determine the sex of the fish. This will help you to ensure that you’re buying a male and a female fish for the purpose of breeding.

How to Tell Male and Female Angelfish Apart

Telling male and female angelfish apart isn’t as easy as some might think. This doesn’t mean that it’s impossible, though.

The first thing to look at will be the breeding tubes. Both males and females have breeding tubes, but they look different depending on the sex of the fish.

A male angelfish is going to have a breeding tube that is pointy. In some ways, it looks like a sharpened pencil.

The breeding tube will be much thinner than the breeding tube of a female fish. Female breeding tubes are substantially wider and they’re also blunt instead of being pointy.

You can locate the breeding tube on the fish by looking at the underside of the fish. It should be possible to identify the sex of the fish simply based on the breeding tube.

There are other characteristics that can help you to identify the sex of the fish as well. Males are typically going to be a good bit larger than females, and their bodies should be round.

Females have smaller bodies and also have angular belly lines. Males have forked ventral fins while the frontal fins of females will be very smooth.

When you look at the forehead of the angelfish, it should feature an enlarged bump if the fish is male. Females have sloped foreheads.

If you put all of this information together, then you should be able to determine the sex of the fish. Once you get used to spotting these differences, it won’t feel nearly as hard to tell the difference between a female fish and a male one.

Behavioral Differences

Behavioral differences between males and females can help to identify which is which. If you’re really bad at spotting the difference between the physical characteristics of the fish, then you might be better at keeping an eye out for behavioral differences.

Males are going to be significantly more territorial than females. If you note that one of the fish is fairly aggressive, then there’s a good chance that it’s a male.

Females will become more aggressive when they’re protecting their eggs and fry. So if you see a fish being aggressive in another situation, it’s likely that you’re looking at a male angelfish.

Males will also try to get the attention of females to form mating bonds by fanning out their fins. He will then shake his fins, and the female will shake her fins back in response.

Since the female doesn’t fan its fins out, this can be a way to tell the difference between male and female angelfish. Of course, it might not be practical to wait until the fish are ready to form a mating pair to finally tell the difference between each fish.

Luckily, you’ll be able to keep an eye on how the fish swim, too. Females and males actually swim quite a bit differently.

Males swim with their bodies positioned horizontally from mouth to tail. Females hold their mouths higher than this at the center of the tail.

You can get pretty good at spotting the differences in the way that the fish swim through regular observation. This might be an easy way to tell which fish is which at a glance.

Wait Until the Fish Are Old Enough to Try to Distinguish the Sex

Trying to distinguish between male and female fish too early on will be tough. This is because the fish aren’t developed enough to truly make it easy to tell.

As the fish continue to age, they’ll mature and develop the proper characteristics mentioned above. When the fish are very young, they’re going to pretty much look the same.

So if you can’t tell the fish apart for the life of you, then it’s possible that you need to wait until the fish age a bit. Fish that are younger than six months old can be difficult if not impossible to tell apart.

After six or seven months have passed, you should be able to use the advice from earlier to tell which fish is male and which is female. The breeding tubes will be able to be recognized, and you won’t have to guess which is which any longer.

It should be noted that not everyone buys very young angelfish. You can choose to buy mature angelfish so that you don’t have this problem.

In fact, if you plan to breed the fish, it might make more sense to buy fully matured fish. This way, you’re ensuring that you’re able to purchase a male and a female angelfish.

Getting Angelfish to Breed

Getting angelfish to breed shouldn’t be too tough overall. Angelfish will even form mating pairs and breed in a community tank setting.

Just ensure that you have both a male and a female angelfish in your fish tank. The two fish should eventually form a mating pair.

This happens when the male starts fanning out his fins and shaking them at the female. The female should shake her fins in response.

Eventually, the two will lock lips and shake each other. This signifies that the mating bond has been formed.

You’ll start to see the two fish cleaning an area of the fish tank. This is in preparation so that the female will have a good spot to lay her eggs.

Once the female angelfish lays her eggs, the male will pass over the eggs to fertilize them. This makes the eggs viable, and nothing will happen if the male doesn’t fertilize the eggs.

Now the two fish will work together to protect the eggs. If the fish are in a community tank, then they’ll chase other fish away from the eggs so that they won’t get eaten.

Many choose to put the mating pair in their own breeding tank. This makes things less stressful for the parent fish so that they can just focus on caring for the eggs.

The parent fish need to keep the eggs clean and provide them with oxygen. If all goes well, then the eggs should hatch within sixty hours.

At this point, the angelfish fry will be in the wiggler stage. They’ll remain attached to the yolk and will receive nutrients from it for five days.

After five days have passed, the angelfish fry will be free swimmers. The parents should protect the fish until they form fins.

Many note that it’s best to separate the parent fish from the angelfish fry before a week has passed. The parent fish might eat some of the angelfish fry if they nip at them too much.

The Rusty Angelfish Can Change Gender

The angelfish that is capable of changing gender is known as the rusty angelfish. This is the colloquial name for the fish and it is also known as Centropyge ferrugata.

Researchers observed rusty angelfish and noted that smaller males would change gender after losing a contest to a large male. It would start with the smaller male starting to perform female mating rituals, and then it would fully change its gender to female.

Interestingly, even the color of the dorsal fin changed on the fish. Males have a different color than females do, and this color changed when the fish changed gender.

When the fish fully changed gender, it was capable of mating as a female normally would. This is definitely interesting, but it’s not something that only this fish can do.

There are plenty of other fish that are capable of changing gender. You might have heard of clownfish deciding their gender.

With clownfish, the larger fish will become the female while the smaller one will be a subservient male. It’s quite intriguing to note the differences between various fish and how they go about doing things.

You can put the angelfish parents back in the community tank or you can move the angelfish fry to a separate tank. Remember that angelfish fry need to eat small food such as microworms and freshly hatched brine shrimp.

It can be very satisfying to breed angelfish, but don’t be too frustrated if the parent fish eats some of the eggs the first few attempts. This is known to happen, and the parent fish do get better at protecting the eggs and the angelfish fry as they gain experience.

Final Thoughts

After learning more about angelfish, it should make it easier for you to feel confident caring for them. The angelfish that you can buy from most pet stores won’t be capable of changing gender.

These are freshwater angelfish that are either going to be male or female. You might not be able to tell which is which if the fish is too young, though.

Once a fish reaches six or seven months old it’ll be fully developed. At this time, you’ll be able to note the characteristics of the fish to determine if it is male or female.

You can tell the difference by looking at the breeding tubes of the fish. Since these tubes will be different between males and females, it’s an easy way to distinguish the sex of a fish.

It’s also possible to look at other physical characteristics to tell the difference. Males are larger and rounder than the smaller female angelfish.

Very few angelfish are capable of changing gender. The one species that is for sure known to be capable of this feat is known as the rusty angelfish.

This is a saltwater angelfish that isn’t as commonly sold. These fish can change to become females if they lose a contest to a larger male.

Other fish can do this in nature as well, but sometimes the circumstances are different. Now that you know this, maybe it’ll make it easier for you to ensure that you get a male and a female angelfish in your tank.

If your goal is to breed the fish, then you’ll definitely need to purchase one of each sex. Enjoy your angelfish and do your best to care for them so that they can breed and thrive in your tank.

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