Why Do Guppies Give Birth To Dead Fry?

For guppy breeders, one question frequently asked is:

Why do guppies give birth to dead fry?

Well, to be fair – there are numerous reasons why your guppies are giving birth to a random dead fry. One main reason for the cause of death would be stress and I’ll tell you why.

In this article about guppies giving birth to dead fry, I’ll be covering:

  • The basic information about guppies
  • Breeding your guppies
  • Learning how they breed
  • The reasons why they give birth to dead fry(s)

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Basic Guppy Information

why do guppies give birth to dead fry
Photo by Zucky123

Guppies are tropical freshwater fish, which are native to South America and belong to the Poeciliidae family. There are more than three hundred varieties of Guppies, and they come in various colors, shapes, and sizes.

Did you know? 💡 Their name is derived from Robert John Lechmere Guppy, who found these fish in 1866 in Trinidad.

Guppies are also known by a few other names such as “The Rainbowfish“, because of the variety of colors they are found in. These fish are also called “The Millions Fish” because of their fast breeding rate.


Breeding Your Guppies

why do guppies give birth to dead fry
Photo by basuka on Pixabay

Having a decorative glass provides a unique space for the guppies to give birth to their young ones and for the fry to hide in a safe area. Generally, the guppies breed a lot.

They are not shy, and they produce with or without your input. There are various ways a fish can reproduce.

Did you know? 💡 Guppies are ovoviviparous, which means that the females grow the baby fish inside their bodies in an egg.

The egg sac is then used for nourishment by the baby fish.

Once the fish is about three to five months, they are ready to start breeding as well. That’s how quick it is!

There are a few telltale signs in them, such as:

  • Coloring: the males are much brighter and more vivid looking as compared to the females
  • Modification of the anal fin: there is a modified anal fin in males known as a gonopodium. It is narrower and longer than a female’s anal fin. Some of the species even have a pair of claws on the tip.
  • Size: the females are larger than the males.
  • Spot: Sometimes, the females have a gravid spot just behind the anal fin, which is a dark spot, and it gets darker during their pregnancy.

Four Reasons: Guppies Giving Birth To A Dead Fry

why do guppies give birth to dead fry
Photo by basuka on Pixabay

It is possible at times for you to notice that the fish has given birth to healthy and alive looking fish and after a few days give birth to a dead fry.

This is common with the guppy and can be caused by a few possible reasons.

It may be due to environmental stress, which could have caused it to abort the fry, or for the fry to have become stillborn.

In such a case, it is best to check the water parameters and maybe add some medications in the water for the fish during her pregnancy term.

Giving birth to a dead fry can also happen if the fish is being harassed by other male guppies or other fish in general who want to get more babies in.

Moreover, there are other possible reasons, as well:

Reason 1. The fish could have conceived the dead fry at the same time as the other fish, but they may not have been born right away because they had already died in the womb.

There is usually more emphasis on the alive ones from the mother’s body and to give birth to them safely and then get rid of the dead ones.

Reason 2. The other scenario could be that the fish may have conceived the dead fry later as compared to the alive ones. It might have been a near abortion or full-term or less than full-term abortion of the dead chip.

It is possible that they were genetically defective or could have been some other problem as well.

Reason 3. It is possible for the guppies to give safe birth to some fry and a few others the next day and so on. Usually, they give birth to all of them in one go, within a span of a few hours.

Then the fish fertilizes more eggs and then is pregnant once again for about a month, and then gives birth again.

Reason 4. Stress can also be one of the factors due to which a guppy can give birth to a dead fry. It also depends on the water quality as well as factors like social stress.

Moreover, experts also believe that if the pregnant guppy was moved in the last week of her pregnancy, by holding it in a net, then this could have been a problem as well.

Usually, a pregnant guppy is quite significant in size, and the holding net cannot hold the fish comfortably.

If you do want to catch her, it is best to do so in a net and then keep it underwater and then move it in a cup, and it is better to do so in the early stages of her pregnancy.

In case you would want to move the pregnant guppy to a “maternity tank” for a safer birth and to keep the newborn fry safe, then you should fill the tank with water, which is from the main tank so that there is no water chemistry stress.

In fact, you can also add in proper salt to the water, which will be suitable for the fish and the fry.


Thoughts on Guppies

why do guppies give birth to dead fry
Photo by sufeca on Pixabay

Guppies are peaceful and colorful fish and are ideal for beginners as well as for experienced fish keepers.

They are available in a wide range of colors and make the perfect first time fish as they are appealing with their different shapes and sizes.

It is essential to ensure that the water is always kept clean for them so that they are provided with a well-balanced diet to be happy and healthy in your tank.

Usually, the process of breeding the guppies is quite a simple task, and many times you may experience the females giving birth to a dead fry as well as alive and healthy ones.

The above reasons can help you prevent that in the future.


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