How Does Guppy Reproduce: Your Ultimate Guide

Guppies can be found in salt water, fresh water, and brackish water. They are generally small fish that have an operculum which they use to close their gills when they are not feeding. The guppy is a tropical fish and is found in both freshwater and marine habitats. But how do they reproduce?

In this article, we are going to discuss how guppy fish reproduce as well as the things you have to take note of during their pregnancy period.

How Do Guppy Fish Reproduce?

The guppy provides birth to its fry in order to propagate. Because all of these baby fish emerge from one body shortly after fertilization into hatchlings who imprint as they begin life, they don’t have to depend on sunlight or water conditions. Guppies do not lay eggs; instead, they live with their eggs, which reside in their bodies until the fry are old enough, at which point the female delivers birth to her fry. Because they are laid by the mother guppy rather than laying eggs, the fry of guppies is more developed than most fish. The eggs in the womb are fully formed, and the fry is born.

Having at least two male guppies in the same area as your pregnant female is a brilliant idea. It should be noted that it is normal for most fish to act bizarrely when getting close to the birthing process, so don’t feel too bad if some of the other roommates start swimming away.

Guppys in freshwater aquarium with green beautiful planted tropical. fish in freshwater aquarium with green beautiful planted tropical.

Can Guppies Self Reproduce?

Yes, guppy fish can actually self-reproduce. This might seem impossible but it turns out female guppies can hold male guppy sperm for more than 10 months which can lead to unexpected pregnancies which look like reproduction without any help.

During the mating season, when two guppies of different sexes want to mate, the male will swim towards the female to release his sperm. The male guppy’s anal fin is fully extended and when touched, it moves very fast. When the male gets close enough to a female’s anal fin (or vent), he extends his gonopodium towards her anus in order to insert himself into her body cavity for the fertilization of eggs. After mating, the male expels ciliated sperm out through his anal fin which will allow swimming around just outside of the female’s cloaca.

How Fast Do Guppies Reproduce?

A female guppy will give birth to her fry about every 30 days. If you keep the same populations together, then you can expect to see some crowding in a tank. Still, there are still a few different theories in regards to how fast pet fish breed. In addition, studies have been done in the past where guppies were placed in individual tanks with varying densities. The tank with the highest density had twice as many females as males and they spawned once every 30 days. On the other hand, the tank with the lowest density had twice as many males as females, and the guppies breed once every 45 days.

How Long Are Guppy Pregnant?

The length of a guppy pregnancy differs depending on each individual’s different species and genetic makeup, but on average, a guppy’s gestation period lasts around 21 to 30 days. During this time, the mother will carry her baby within her pelvic fins and will birth to around 50 to 60 children at a time. Despite the fact that the baby guppies are little at first, they will develop quickly and can start swimming a few days after birth.

How to Take Care of Pregnant Guppy

Guppys in freshwater aquarium with green beautiful planted tropical. fish in freshwater aquarium with green beautiful planted tropical.

Clean Water

The number one thing you can do to take care of a pregnant guppy is to provide her with clean water. While the mother will filter food for her young, dirty water can still cause harm. Make sure that your guppies have access to plenty of fresh, clean water by changing their tank daily and adding enough quality aquatic plant life to cover any surface area.


Providing your guppy with a balanced and nutritious diet is key to ensuring she stays healthy during her pregnancy. Along with offering plenty of calcium and other essential nutrients, make sure to feed your fish lots of plant-based sources of protein such as algae or peas. In addition, avoid feeding your pregnant guppy any harmful junk foods or sugary treats, as these could do more harm than good. And finally, be sure to keep a close eye on your female guppy in order to ensure she’s giving birth safely and quickly.

Tank Mates

Making the decision to have a baby can be difficult, but it’s even harder when you don’t have any tank mates to help take care of your guppies. Unfortunately, guppy pregnancies are often endangered by other fish who may not understand that these babies are harmless and won’t bother them. If you do decide to add another fish into your aquarium during this time, please make sure they’re from a compatible species so your guppies will have some support.


The temperature of the water during a guppy’s pregnancy is extremely important for their health and development. Too cool of a temperature can cause the female to lose interest in breeding, while too warm of an environment can lead to complications during birth. It is best to keep your guppies’ tank at around 77 to 79 degrees Fahrenheit (25 to 26 degrees Celsius) during this time.


Adding equal levels of light and heat to a pregnant guppy’s tank can also be of benefit. While it is best for her not to see any lighting at all during the early stages, as this may cause distress and stress, once she has given birth you will want access to both light and warmth.


If your female friends are getting along in their new community or tank together prior to baby-making (they should), then there shouldn’t be any threat of aggression from other females. However, if the female is in a tank with another male or multiple males then there may be competition for a space that her baby will share later on when it is time to swim around and feed. If this does happen you can have 2 or more guppies instead for your pregnant fish’s babies, however, keep them separate so as not to distress any others than yourself.

Stress Management

During pregnancy, it is very important not to handle or disturb the mother unless absolutely necessary because doing so could result in the baby being displaced from safety at a critical time during development! This triggers amniotic sacs that surround your juvenile; thus depriving them of oxygen and causing their embryonic membranes to break apart.

What Do Baby Guppies Look Like?

At birth, your guppy fry may look like an overgrown tadpole with its tiny tail/fin (called a caudal fin in freshwater fish). As they develop and their respiratory system matures, your baby guppies will grow fins around the dorsal surface of their bodies that “fin up.” Do not be alarmed if new tail fins start appearing sporadically on the backside portion of your juvenile’s body. This is common behavior amongst adult males which allows the male to identify other males from rivalries by how developed his swimming muscles are.

Over the course of 3-5 days, guppies will grow a precocial body that may look visually similar to an adult’s. At this point, it is safe (and beneficial) for you to handle your newborn and provide weight even though they’re very tiny.