How Do Guppies Breed?

Kelly Roper
Guppies in a tank

Guppies are livebearers, which means that their babies are born live, not from eggs like many other types of fish, including goldfish. Guppies also tend to breed rather freely, so you can quickly go from a single pair or a trio to dozens of pet guppies if you choose to keep males and females together. Find out more about how guppies breed.

The Act of Breeding

The breeding process is fairly straightforward and lightening quick. When conditions are right, a male guppy will try to approach a female with the goal of inseminating her. The female rarely remains still for this activity, and she typically darts away and a chase ensues. When the male gets close enough, he extends his gonopodium towards the female's anal vent.

The gonopodium is actually the male's anal fin. It is shaped like a rod and slightly pointed, and it's located just behind his ventral fins. The gonopodium contains a tube that actually delivers packets of sperm to the female. The breeding takes less than a second, and it looks just like he is stinging her at her vent where her gravid spot is located. This is the dark spot just behind the female's abdomen.

Although the breeding is extremely quick, numerous breedings will take place to ensure the female has been fertilized.

Gestation

The gestation period for a guppy varies a bit, and how long she remains pregnant depends a lot on her environment. The average length of the pregnancy is between 22 and 28 days. However, a female can remain pregnant even longer if her water is too cold because it slows development of the babies, also known as fry. She may also delay delivery if there are too many fish in her tank harassing her.

Multiple Drops from One Breeding Session

It's an interesting fact that a female can go through multiple pregnancies in succession after the initial breeding. She has the ability to store extra sperm packets from the male, so it's possible for her to give birth about once a month for several months after the birth of the first set of fry. Each delivery is also known as a drop.

Ideal Conditions for Breeding

There's not too much you need to do if you want to encourage your guppies to breed. Just provide the following conditions.

  • Guppies are tropical fish, and they do best in temperatures between 75 and 85 degrees Fahrenheit. Aim for a constant water temperature of 80 degrees Fahrenheit, and this will help inspire your pets to breed.
  • Guppies like hard water, so maintain the pH between 7.0 and 7.6.
  • Offer your guppies some fresh or frozen brine shrimp in addition to their regular flake diet. Feed your fish twice a day, and monitor how much food they eat. You should never offer more than they can eat in five minutes.

Now You Know How It's Done

Now that you understand exactly how guppies breed, it's easy to notice when it happens. If your female's gravid spot begins to enlarge and she looks heavier than ever, you can be certain she is pregnant. Make sure you provide her with everything she needs to support her pregnancy, as well as a safe place to have her fry or she and her tankmates may eat them.

How Do Guppies Breed?