How do Guppies Get Pregnant?

How do Guppies Get Pregnant?

How do Guppies Get Pregnant?

Guppies are readily available at pet stores and at a relatively cheaper price compared to other aquarium fish. They are the most common fresh water fish species and most widely spread tropical fish.

This makes guppies among the most popular aquarium fish that are kept by both beginners and experienced fish keepers. Guppies are easy to maintain, peaceful and have vibrant colors.

They are also known as rainbow fish, due to their vibrant colors and million fish because of their fast breeding rate.

Guppies were naturally found in northeast South America, but they have been spread out throughout the world. In their natural habitat, they feed on aquatic insects, algae and benthic.

Unlike other fish that have limited living conditions, guppies learn to adapt to new environments easily and therefore can thrive in many different environs.

Male guppies are smaller compared to their female counterparts. They, male guppies, also have an ornamental caudal and dorsal fin that their female counterpart guppies do not have.

Guppies are available in different sizes, colors and the shape of the tail. This has resulted from breeding different species of guppies.

Guppies are livebearers, this means unlike many other types of fish that lay eggs and hatch them into young ones, guppies give birth to live babies. If you keep male and female guppies in your tank, you will have many more guppies over time because they are active breeders.

How do Guppies Breed?

How do Guppies Breed?

How do Guppies Breed?

Once guppies reach sexual maturity, it is easy for them to start breeding. Guppies get to sexual maturity between the ages of three to five months. You will tell your guppies are sexually mature and ready to breed by the following signs;

  • Male guppies are smaller than females.
  • Male guppies are more colorful than female guppies.
  • Females have a dark spot behind their anal fins. This is called the gravid spot. This spot gets darker once the guppies are pregnant.
  • Male guppies develop a gonopodium fin. This is a modified anal fin that is lengthier and slimmer than a female’s anal fin. Some guppy species have a gonopodium fin that has a pair of claws at the tip.

The breeding process for guppies is very fast and straightforward. A male guppy approaches a female guppy with the goal of fertilizing her with its gonopodium fin. A female guppy rarely stands still for the process, she will dash away, and therefore a chase follows.

When the male gets close to the female, he extends his gonopodium fin towards the female’s anal vent. The gonopodium fin, which is shaped like a rod and somewhat pointy, is the male’s anal fin. It has a tube that conveys a pack of sperm to the female.

The breeding process for guppies takes less than a second. It appears as though the male is stinging the female at the gravid spot. Although the process is fast, it may require many breeding for the female to be fertilized.

Gestation Period for Guppies

After a successful breeding process has taken place, it may be difficult to tell if your guppy is pregnant or not. However, there are some obvious signs that include;

  • The female guppy’s gravid spot becomes larger and darker.

Female guppies have a gravid spot near the anal fin at the back of the abdomen under the tail. The gravid spot is dark in colour, but it darkens and becomes large when a female guppy becomes pregnant.

  • The guppy grows large and boxier

A pregnant guppy will grow larger, appear to be bulky and have a boxy shape. However, this may not be evident until the female is near the end of her pregnancy.

  • Visible fry eggs

As the end of pregnancy terms gets closer, small eyes of the fry may be visible through the female’s belly skin that is thin and translucent. The eyes are mostly seen near the gravid spot.

  • The female guppy coloring fades.
  • Feeding habits for a pregnant guppy changes. She may either eat too little or eat hungrily.
  • The fish may become more aggressive.
  • The guppy prefers remaining in one spot of the tank, mostly around the heater.
  • The guppy’s fins appear as though they are partly opened and its back has an arched shape.

The average length of guppies’ gestation period is approximately 22 to 28 days. However, the gestation period will vary depending on the conditions of the tank.

Caring for a Pregnant Guppy Fish

Caring for a Pregnant Guppy Fish

Caring for a Pregnant Guppy Fish

The gestation period for a guppy is fast, less than a month, therefore the pregnancy stages advances too fast. To ensure your guppy has the necessary requirements during the pregnancy, it is important to ensure the tank conditions remain favourable. Proper care is critical for a pregnant guppy.


Guppies are tropical fish, therefore the best temperature range is between 75 and 85 degrees Fahrenheit. Maintain water temperatures at a constant 80 degrees Fahrenheit to inspire the guppies to breed. During pregnancy, cold water will slow down the development of the fry, therefore, keep the tank warm to keep the female from being pregnant for too long.


A pregnant guppy needs good nutrition to sustain herself and the growing fry. Due to the fry developing in her belly, she is unable to feed well. Therefore, provide three to five small meals for the guppy throughout the day. The meals should be little, only what the guppy will eat and finish, to ensure the leftover food does not foul the tank. It is advisable to give your guppy a variety of good nutrition. Food such as live or frozen brine shrimp, high quality flake food, freeze dried bloodworms and spirulina flakes are good nutrition that can be offered on a daily basis to a pregnant guppy.

Clean Water

The water tank should be cleaned regularly to protect the female guppy from illnesses. Illnesses and diseases can affect the development of the fry or hinder the process of pregnancy. The tank can be fouled by leftover food, therefore, make sure you have a functional filter to clean the water.

Tank Mates

If the female guppy is stressed or senses potential danger in the tank, it will stay pregnant longer. Make sure the tank mates are not harassing the pregnant guppy. When the guppy gets closer to giving birth, you can isolate her in a different tank to ensure she is not stressed.  However, long hours in isolation can also increase stress levels. Put the guppy in a different tank only when she is almost giving birth. Increased stress levels can also reduce the pregnancy period leading to miscarriage or unplanned abortion.

Guppy Fish Giving Birth

When a pregnant guppy is ready to give birth, she will seek a solitary space in the tank and remain still or slow. However, there are no definite indicators that the guppy is ready to give birth.  Most guppy breeders choose to move a female guppy into a separate tank to give birth in order to protect the fry.

Young guppy babies are at a risk of being eaten by a stressed or hungry female guppy. Therefore, as soon as the guppy gives birth, she should be put in isolation to recover before being reinstated into the main tank.

It takes between two to six hours for a female guppy to give birth to all the fry on normal circumstances. However, the process may last up to twelve hours in case there are difficulties. In some cases, the mother delivers a few fry, stops and resumes few days to deliver the remaining fry.

Guppy Fish Giving Birth

Guppy Fish Giving Birth

When the fry are born, it is important for them to be fed often and taken care of in a separate tank. They should be fed at least five times a day, especially within the first four weeks, when they go through their greatest development.

The fry are small, therefore their food should be very small, for instance, pulverized flakes or freshly hatched brine shrimp. When the fry are fed well, they will grow in good health and stronger each day.

Remember guppies get to sexual maturity at four weeks and become sexually active at the six week mark. Therefore, if you do not want them to reproduce, separate the female and males guppies to prevent them from breeding.

Guppies are active breeders hence the name million fish. Since guppies get pregnant when they are so young, and they can live up to three years, one guppy can give birth up to two thousand or more babies in her lifetime.

Female guppies have the ability to store sperm from males for up to one year, therefore, with good tank conditions and good health, a female guppy can get up to eight pregnancies from one fertilization. After giving birth, a guppy can become pregnant just hours after.

Understanding the gestation period, knowing how to properly take care of a pregnant guppy, keeping the water clean, and providing a well balanced diet, guppy breeders can enjoy nurturing and growing guppies for many years.

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