How Long is a Guppy Fish in Labor?

Guppies are rather prolific breeders, with one female capable of producing in excess of 100 fry every month. Combine this with the breed’s amazing color variety and pattern diversity, and you can see why guppies are so popular among aquarium owners.

Under the right circumstances, guppies will produce offspring roughly every 30 days. This is true for a balanced guppy population with healthy females and a balanced male-to-female ratio.

But other factors may influence your guppies’ ability to have offspring. Today, we will discuss guppy breeding, the number of fry it can produce, and how to care for them post-birth.

How Many Fry Can A Guppy Produce?

The number of fry a guppy female can produce will vary wildly. You should expect to see your guppy females producing between 2 and 200 fry with each pregnancy.

Several factors will influence the number of fry that a healthy guppy will produce. These include:

  • Sexual maturity – While females become sexually mature at 3-months of age, this is far from their sexual prowess. Females will generally produce a low number of fry at this age, typically between 2 and 50 at most. They will become sexually proficient at 6 months of age, when the number of fry may increase dramatically. You should expect your 6-month-old guppies to deliver between 20 and 150 fry every month. Some will consistently deliver over 100 fry for some of the reasons that I am about to explain.
  • Genetic predisposition – Guppies will inherit a variety of traits from their parents, including physical characteristics, overall health, predisposition to illness, and breeding proficiency. Generally speaking, female guppies will follow their mothers in terms of breeding capabilities. If their mother was a prolific breeder, so will the daughters. The same pattern works for the other extreme, where females with poor breeding capabilities will give birth to fry with similar tendencies.
  • Environmental factorsGuppies will breed more in warm, safe, and nutrient-rich environments. Their gestation period will also shorten due to the advantageous environmental conditions. Generally, guppies give birth to fry every month, with the gestation period varying lasting between 21 and 35 days. Some of the factors influencing the duration of the gestation are environmental, which means you can control them.
  • Old age – Guppies will give birth to fewer fry as they advance in age. By a year and a half in age, the guppy has already burned half of its lifespan. You should expect your guppies to deliver a lower number of fry as they get older. At one point, guppy females will also reach menopause, at which point they won’t get pregnant anymore.

How Many Times Will a Guppy Female Give Birth?

There is no standard number to mention when it comes to guppy birth rates. As a general rule, however, a guppy will deliver close to or in excess of 1,000 fry during its lifespan.

This number will vary depending on environmental factors, fish illness, genetic makeup, food, etc.

It’s also worth noting that guppies, both males, and females, will experience menopause and andropause, respectively. Like humans, however, there is no specific age when this phenomenon takes place. Some guppies may give birth to healthy fry until the moment they die, while others may stop a year or more earlier.

What Is The Gestation Period For Guppies?

Guppies’ gestation period will vary between 21 and 30 days, but it can go beyond those limits in some cases. Female guppies have been known to gestate for 35 days in some cases.

Some of the factors that will lower or increase the gestation period include:

  • Coldwater – If the water temperature drops under what a guppy would consider comfortable, the gestation period will increase. This is because giving birth to fry in cold waters can kill them. Guppies thrive in waters with temperatures varying between 72 to 80 degrees F. As the temperature drops, the guppy’s biology will change, increasing the gestation period accordingly.
  • Hot water – Warmer waters will have the opposite effect, lowering the gestation period significantly. That’s because warm waters signal the guppy that the environmental conditions are optimal for breeding. Just make sure you don’t increase the water temperature beyond your guppies’ comfort threshold, or it could backfire. Now you know what to do to increase your guppies’ reproductive rates.
  • Protein-rich foods – Feeding your guppies protein-rich foods may boost their breeding rates and decrease the gestation period slightly. The abundance of nutritious food informs the guppies that their fry will have plenty of resources at their disposal. Just don’t exaggerate with the protein, since adult guppies can have problems due to protein and fat-filled foods.

How To Care For Pregnant Guppy Females?

First, you must identify the pregnant females. You can easily tell which is pregnant by the inflated abdomen and the visible pregnancy spot. This is a dark area in the rear part of the abdomen that all pregnant guppies will display.

Once you’ve identified the pregnant guppy, I suggest moving it into a separate breeding tank 2 weeks into the pregnancy. As you already know, the gestation period will last around 30 days, usually less. A 2-week-old pregnancy is already visible, and your guppy may only have one week left until delivery.

Moving it into a different tank will provide the female with a safe, comfortable, and peaceful environment to bring its pregnancy to term. You no longer need to fear the female experiencing stress due to males poking at it or annoying it with their sexual energy.

I also recommend feeding the female a balanced diet and only provide small amounts of food. Pregnant female guppies won’t eat as much due to their extra ‘luggage’ taking up all the space.

And don’t forget to set the new tank to the same water parameters as the main one. Moving the female into an environment with drastically different living conditions can shock and even kill it.

You can even increase the water temperature slightly to make the female more comfortable and reduce the gestation period.

How To Care For Guppy Fry?

Your priority should be to move the female into a separate tank. This will serve as a home for the future fry population. The breeding tank should have a setup similar to the main one. This includes adding hiding spots, caves, plants, and various decorations to keep the fry safe and comfortable.

A reliable filtering system is also key to preserving the water quality and ensuring optimal oxygenation.

One keynote to make regards the dieting. Guppy fry have similar nutrient requirements to adults with several slight differences. Aside from eating twice as often (3-4 times per day), guppy fry also require more protein and fats than adults.

This is because their bodies are growing at faster rates and require a surplus of calories as a result. I’ve written several articles on guppy feeding behavior, detailing various recipes and food options to use, including for guppy fry.


Guppies tend to breed a lot, which is why it’s essential to know what can influence their pregnancy rate and overall breeding proficiency.

This information can help you decide how to control your guppy population or even breed guppies for profit. This goes into the selective breeding category, which consists of several high-end techniques.

Now you know how guppies breed, how long the gestation period lasts, and how to care for them during that period. This makes you a qualified guppy owner capable of producing and maintaining a thriving guppy population.

avatar Noah
I’m Noah, chief editor at VIVO Pets and the proud owner of a playful, energetic husky (Max). I’ve been a volunteer at Rex Animal Rescue for over 2 years. I love learning and writing about different animals that can be kept as pets. read more...

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