How To Breed Guppies – The Ultimate Guppy Breeding Guide

Last Updated on August 1, 2021 by cmoarz

Learning how to breed guppies is super easy, at the end of the day, a male and a female guppy will eventually breed on their own if in the same aquarium. But there are a lot of things you can do to increase the spawn rate and get the best out of your breeding.

This article will tell you everything you need to get started breeding guppies with ease.

Setting up the breeding tank for guppy fish

You don’t need to do this in a separate breeding-only tank, you can do it in your main tank, but you need to be prepared to remove fry if anything else in the main tank will eat them.

You also should keep in mind guppies breed very very quickly and their gestation period is short, only about 20-30 days. Your main tank could get flooded very quickly with guppy fry.

On the other hand, a breeding tank is an excellent idea.

Standard benefits:

  • You’ll have a dedicated tank for breeding.
  • Guppies will be safe from predators in the main tank.
  • It’s easier to keep track of everything.
  • It’s easier to keep clean and to feed them.

Emotional benefits:

  • Enjoy watching your many fry grow up and thrive in their own environment.

Guppy breeding tank setup:

  • 75-78° Degrees Fahrenheit, 80° once ready to breed
  • pH between 7.0 and 8.0
  • Many hiding places for the fry, can be plants or decorations
  • Optional: Breeder box, some guppies are cannibalistic and will eat their own fry
  • The substrate is optional, but you should have something in there, gravel or sand.
  • A filter sponge

The tank will be very similar to any other tank you’ve set up, but the temperature might be a bit higher than you are used to.

The water quality is a lot more important in this tank, you need to keep the temperature as stable as possible and the filter should be a good biological one.

Guppy breeding tank maintenance:

Weekly partial water changes (up to 5-10%), More if you don’t have plants to eat up nitrates.

Water testing for pH, ammonia, nitrites, and nitrates, and other important water parameters.

Vacuum once a month to get the gunk off the aquarium gravel.

Always be checking for fry! You need to get them into a fry box or breeder box asap.

How many female and male guppies are in 1 breeder tank?

You can add as many as the tank can hold, but at minimum, we recommend 1 male guppies for every 2 female guppies.

This will cut down on aggression and make them spawn more often.

If you have more males, try to always keep the same ratio of 1 male to every 2 females, although it can go as high as 1 male for every 6 females if you choose.

Removing the Fry from their Mother

If you have a breeding tank for these fish, then you’re going to need to remove the fry from their mother. This is because guppies can be cannibalistic and will eat their own fry if left to their own devices.

If you don’t have a breeding tank and are using the main aquarium, then it’s not necessary to remove the young from the parents. However, it is still recommended that you do it for the sake of productivity. Remember, your main aim here is to breed more guppies!

You can avoid a lot of the hassle by giving the guppies small hiding places that the adults can’t get to, or by placing them in a breeder box so they have time to safely grow out a bit.

Tankmates are optional as long as they’re friendly and not active hunters. You’ll need to remove any tank mates with a mouth larger than an adult guppy’s body. Some fish bigger than a guppy might eat the fry too, such as cichlids or some tetra fish. 

How Long Are Guppies Pregnant

A guppy will remain pregnant for 20 to 30 days before giving birth to about 20-40 fry, with some variation.

The first two weeks after birth they will be known as fry because of their size, but that’s just a nickname for newborn fish. They are actually juveniles at this point as they grow quickly and become adults in a few month’s time.

Be careful not to confuse the pregnant stage with the post-birth phase.

A lot of people mistake the post-birth phase for the pregnancy phase. The signs are very different though.

How to Tell if a Guppy Is Pregnant

Belly Bulge: The female guppy will gain a large bulged out belly during pregnancy, she might even look a bit fat.

A swollen pregnant belly is one of the first signs that your female guppy is indeed expecting fry soon!

Black spot (Gravid spot): This won’t show up right away, but after about 2 weeks a black spot known as the gravid spot will develop on the belly of pregnant tropical fish including a guppy.

It may change colors as the pregnancy moves forward. Eventually, you may be able to make out the baby guppies inside the spot.

Swimming in place: Swimming in place is a very common indicator of near-term pregnancy.

You can see them swimming in the same place over and over again as if they were using a treadmill. This only happens during pregnancy, it doesn’t happen during other stages of life.

How Often Do Guppies Have Babies

Female freshwater fish guppies reproduce approximately every 30 days with litters that are born ~20 times throughout their lives. However, as the female guppies age, they sometimes skip a litter or two and can even stop reproducing for extended periods of time.

How Long Do Guppies Stay Pregnant

This will highly depend on the species of the guppy fish. For average sake, normally it will be between 20-30 days.

After which they will give birth to 20-40 babies on average. Again, this is only about the regular female guppies. If you do have a rare one that can skip an entire cycle or two then it could be a while before she gives birth again.

How Many Babies Do Guppies Have In One Birth

It’s very rare for a guppy to have anything less than 20 fry babies. There is no guarantee that it will ever happen, but sometimes it does.

If you’re really lucky, you can end up with 50 or more baby guppies after just 1 birth. However, this is highly unlikely. Expect on average of between 30 and 40 baby fish though when breeding these types of tropical freshwater fish.

How Long Does It Take for Guppies to Give Birth

On average a guppy female will be pregnant for 20-30 days. Insemination is instant and you might miss it – the male simply bumps into the female and the job is done after giving her a chase until she is exhausted.

Giving birth will happen much slower, and she will deliver about 20-30 babies over a several-hour period.


Owner of and also owner of actual Aquarium Gravel believe it or not! ;). Setting up beautiful aquarium sceneries and habitats since I was very young. Enjoy!