How Long Does It Take For Guppy Fry To Show Their Gender?

How Long Does It Take For Guppy Fry To Show Their Gender

Aww, did your guppy fish just deliver babies in the tank? Isn’t it amazing to know you have way more guppies than you can imagine? Are you excited to see all the good things that breeding and guppy babies bring into the tank? I know you have more questions than I do, and first and foremost, aquarists, beginner or experienced, wonder about the gender of guppies to maintain the male to female ratio. So, with a successful breeding season and tank full of babies, you’re wondering how long it will take the guppy fry to show their gender, aren’t you?

The good news is that you won’t have to wait very long at all! In fact, most guppy fry will start to show signs of their gender by the time they are three weeks old. After that, the sex becomes prominent with the tell-tale signs like body size, tail, dorsal fins, gravid spot (in females), and anal fin.

Let’s look into detail about how to tell the difference between male and female guppies and the time the sign becomes more prominent. In this blog post, we will answer that question for you. Keep reading to learn more!

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Do Guppy Fry Show Gender Immediately After They Are Born?

No, Guppy fry takes a few weeks to develop and show their gender. Honestly, you cannot even differentiate if these babies are guppy fry or some tadpole species. They are that small and unnoticeable.

So, do not get too excited yet when your female guppy gives birth. You still have some waiting to do until you can see if you have more males or females in your fish family.

How Long Does It Take For Guppy Fry To Show Their Gender?

The million-dollar question- how long does it take for guppy fry to show their gender? Within three weeks, you should be able to see if your fry is male or female.

During the first week, the fry will not have any distinguishing characteristics. However, by the second week, you might see a small bump on the dorsal fin of males.

This is called gonopodium, and males will use that to fertilize females when they are ready to mate. If you see this, then congratulations! You have a little male guppy on your hands.

How Can I Tell If My Guppy Fry Are Male Or Female?

Now, about all those tell-tale signs I was talking about earlier. How can you tell if your guppy fry is male or female? Well, here are some things to look for:

Size:

Males are usually smaller than females. This difference is more pronounced when they are adults, but you might see a difference even when they are fry.

Shape:

Females tend to have a more rounded body shape while males are slimmer.

Color:

Males tend to be more colorful than females. This is especially true for fancy guppies. On the other hand, females usually have muted colors.

Fins:

Males have longer fins than females, especially the dorsal and ventral fins. The anal fin of a male is also shaped differently. It is narrow and pointy and is called a gonopodium. This fin is used to transfer sperm to females during breeding.

How Long Do Baby Guppy Fish Take To Grow?

Oh, how we wish these fry grow up quickly so we can see their beautiful fins and color! But alas, it takes time for fry to grow into healthy juveniles and eventually adults.

Here is a rough timeline of how long it takes for baby guppy fish to grow:

  1. Fry- Day 0-30
  2. Juvenile- Day 30-60
  3. Young- Day 60-120
  4. Adult- Day 120-180
  5. Old- Month 24+

Guppy Fish Growth Stages

You need to understand the basics of guppy fry development to answer the question of how long it will take before you can start sexing them.

Guppies go through four growth stages: fry, young, juvenile, and adult.

Stage 1: Fry

These are the newborns that have just been born. They are very small, and their bodies are not fully developed yet. So, you need to feed guppy fry healthy yet crushed food if you want to see a proper growth rate.

Fry are born without any color and remain that way for the first few weeks of their lives. During this time, they’ll start to develop their gender characteristics.

Fry are the smallest stage of guppy growth. They are born without tail fins, and their colors are not yet fully developed.

At this stage, they are very delicate, and you need to keep them in warm, clean water. Also, this is the stage where you have to feed guppies more often than usual.

Stage II: Juvenile

At about the three-week mark, you’ll see some coloration in your fry. This is when they transition from the fry stage to the younger version. At this stage, the fry have developed their fins, and their bodies are more elongated.

It’s also around this time that you’ll be able to sex them. They are still growing, and their fins are longer. Their colors might also start to show at this stage.

Stage III: Young

Young guppies are larger than fry and juveniles but haven’t reached their full size yet. They’ll continue to grow and develop their colors during this stage. This stage stretches between the 2nd and 4th months of their lives.

Stage IV: Adult

Guppies reach adulthood around the four- to the six-month mark. By this time, they are fully grown, and their colors will be at their brightest. This is also the stage where you will see aggressive side of guppies during the breeding season.

The fry has now reached adulthood, and their fins are fully developed and are also the largest. The colors of fancy guppies are usually more pronounced in adults. You can expect your guppy to live for two to three years if you take good care of them.

Old (Year Two to Three)

Guppies can live for up to three years, but they start to show their age after the two-year mark. You’ll notice that their colors will start to fade and become less active.

At What Age Do Guppies Get Their Color?

One of the most exciting things about watching fry grow is seeing their fins and color develop. For many people, this is one of the main reasons they want to breed guppies in the first place!

Guppies usually develop their colors during their fry stage to juvenile stage, between one week to four months old. But they will not have colors immediately after females drop them in the tank.

They are nearly transparent for the first few days and start to develop their colors and patterns after a week or more. Clear or light-colored guppies may take longer than dark-colored guppies to develop their full colors.

However, some guppies may not reach their full coloration until they are six months old. In addition, some color patterns, such as the mosaic pattern, may take up to two months to develop.

Does Temperature Affect Guppy Fry Gender?

There is no definitive answer to this question. Some believe that the temperature of the water can affect the gender of guppy fry, while others believe that it does not have an impact.

If you are trying to breed guppies and want to control the gender of your fry, you may want to experiment with different water temperatures to see if it has any effect.

As far as I know, temperature fluctuation can kill guppies, no matter what gender they are. But I am yet to witness the gender reveal depending on the water temperature.

Which Gender Has More Chances Of Survival: Male Or Female Guppy Fry?

Some believe that female guppy fry has a higher survival rate than male guppy fry. This is because female guppies are often larger and have a greater ability to store fat reserves.

Female guppies also tend to be more resistant to disease and can recover from injuries more quickly than males. However, there is no scientific evidence to support this claim.

But, all the claims, myths, speculations, and stories aside, I have seen an equal number of male and female guppy fry survive to adulthood in my aquarium.

Honestly, you will only end up with 25 to 30% of the total fry born on the same day despite their gender. Guppies eat their babies, so if you keep parents and babies together, this number might get lower and lower every minute. The survival of the fittest is what stands here, not the gender, color, or even size.

Do Guppy Fry Change Gender?

Guppy fry cannot change their gender after they are born. So the sex of a guppy stays the same, and they are born with it.

Just because you cannot see it in the first few weeks doesn’t mean it is not there. If you wait long enough, you can determine the gender of your guppy fry.

Do not believe absurdities such as the myth that guppy fry can change their gender. If you want to know for sure, just wait until they are old enough and then check.

If you are trying to breed guppies and want to control the gender of your fry, you may want to experiment with different water temperatures to see if it has any effect. (As far as I know, it doesn’t matter)

Conclusion

In conclusion, guppy fry takes around three weeks to show their gender. However, some may take longer to develop their full colors and patterns. The water temperature does not appear to affect the gender of the guppy fry. Guppy fry cannot change their gender after they are born. Just wait until they are old enough and then check to be sure. Thanks for reading! I hope this was helpful. 🙂

Good Luck!!

Happy Fishkeeping!!

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