Guppies are livebearers.
Instead of the male fertilizing the eggs after the female lays them, fertilization happens inside the female.
She retains the eggs and gives birth to live, free-swimming young, called fry.
Breeding guppies is a really cool experience but it can seem a little overwhelming at first.
It’s not always easy to tell if a guppy is pregnant but it’s important to pick up on it early to prepare to help her during pregnancy and give the fry what they need after they’re born.
Here are some of the important things to know about caring for pregnant guppies.
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How to Tell if Guppies are Pregnant?
One of the first things you’ll notice about a pregnant guppy is a growing belly. There’s a chance that this can be bloating but guppies are highly prolific and breed quickly and often so there’s always a good chance of pregnancy.
If your fish stops eating, rubs herself against plants and decorations in the tank, or starts to shiver or shake, it’s time to suspect that she may be pregnant. Keep an eye on her and watch for more definitive signs.
A clear thing to look for is a noticeable gravid spot. A pregnant guppy has a very noticeable gravid spot in the belly area. It’s usually orange in the beginning and gets darker during the pregnancy, though it changes from light to dark throughout.
As the guppy gets closer to birth, she grows very large and takes on a boxy appearance. At this stage, she’s nearly ready to deliver. You may be able to see tiny black dots in the gravid spot. These are actually the babies’ eyes.
When a guppy goes into labor, you’ll notice body contractions that stop and start. The muscles on the belly tighten and then relax.
Sometimes, guppies hide when they’re about to give birth but they can often be seen in the open, swimming in place. This is one of the most common signs of labor.
Gestation Period for Guppies
The gestation period varies slightly depending on several factors, including the mother’s health and stress level as well as the water conditions of the tank. Generally, it lasts anywhere from 21 to 31 days through 22 to 26 days is average.
Since the gestation period is so short, it helps to know what mating looks like so you can be on the lookout for a possible pregnancy. The male usually chases the female around the tank to exhaust her then inserts his anal fin into the female’s underbelly.
Mating is fast and most guppy owners don’t see it happening. But, if you do happen to notice this behavior, you know to be on the lookout for pregnancy symptoms.
Also, keep in mind that a female guppy doesn’t necessarily have to live with a male to become pregnant. How? Female guppies can actually store sperm for as long as 8 months. That means that she can keep producing babies months after she’s been on her own.
Believe it or not, this is actually a survival mechanism for guppies. Males only live a few months while females can live for about two years. Storing sperm from preferred partners guarantees the female will be able to have babies without a male.
Pregnant Guppy Fish Care
Make sure to feed your pregnant guppy a well-rounded diet to make sure she doesn’t suffer from any deficiencies. Try alternating between flakes, pellets, brine shrimp, blood worms, and algae discs to provide some variety.
Another important thing you can do for a pregnant guppy is minimizing stress. If she gets stressed out, she can absorb the babies and they won’t be born.
An easy way to do this is to get a breeding box to separate the pregnant fish but this, too, can cause stress if not done appropriately. The longer she’s confined, the more stress she’s under so it’s better to wait until the end of the pregnancy to take this step. Breeding boxes are an excellent place for her to have her fry.
It can take between four to six hours for a guppy to finish giving birth but up to 12 hours if she’s stressed. In fact, a stressed mother can take hours to birth only a few fry at a time and the babies usually don’t survive.
A healthy mother, though, delivers one fry at a time, although they come quickly one after the other. There are often short pauses between groups so she can rest. A female guppy can have anywhere from two to 200 babies at a time.
How to Care for Baby Guppies?
There are a few things important things to do keep baby guppies safe and happy.
A Safe Place
Preparing for baby guppies before they’re born is really important because if you don’t have a safe place for them, chances are the other fish in the aquarium will eat them.
A separate breeding tank is ideal. Place the pregnant fry in the tank when she’s about to give birth. Then, remove her and place her back in the original tank when she’s done or she, too, will eat the fry.
If you don’t have a separate tank, you can use a large glass container as a temporary birthing tank. Put the mother in only after she’s gone into labor and return her to the tank after birth. This gives the fry a safe, albeit small, place to grow.
Another great option is a breeding box. A breeding box sits inside the regular tank and is made of mesh or plastic. The best thing about using one of these is that you don’t have to worry about water quality.
Whether you’re moving the pregnant fish during labor of introducing the fry to the tank, the water is the same so the transition is easier.
If you’re planning on leaving the pregnant fry in the tank and not isolating the fry, make sure you give them a lot of hiding spaces. Young guppies have a natural instinct to hide and avoid being eaten. Live plants, moss, and roots really increase their odds of survival in a community tank.
After about two weeks, fry are usually large enough to fend for themselves. They grow quickly and should be big and strong enough to get away from adults after a few weeks have passed.
Newborn guppies are very tiny, only around 6mm long. That said, they grow very quickly and need a lot of food. Their digestion cycle is only 20 to 30 minutes. This doesn’t mean they need to eat every half hour. One or twice a day is enough but if you’re breeding guppies to sell, five to 10 times a day is better.
Guppy fry will eat just about any kind of food but it’s important to prepare it appropriately. Because they’re so small, their mouths are tiny and food should be small enough to fit. Live food is a great option but be sure to use baby brine shrimp or micro worms.
See also: Best Food for Guppy Fish
One benefit to keeping fry in the main aquarium is you don’t really have to worry about water parameters. As long as the adult fish are happy, the fry will be, too.
If the fry are kept in their own tank, there are a few things to consider.
- Keep the temperature at around 80 degrees F if you want to encourage fast growth. They don’t need water this warm but it speeds up their metabolism so they’ll eat more and grow more quickly.
- Do partial water changes often. Because they grow so fast, they load they place on the water is constantly increasing at a fast pace. Doing a 50 percent water change twice a week should be okay for smaller groups. For hundreds of guppies, change the water daily.
- Keep the lights on for about 16 hours a day but no less than 12. Light actually helps prevent spinal deformities but make sure they get about 8 hours of darkness every day to rest.
Introducing Fry to Main Tank
If you’ve kept the fry separate, introducing them to the main tank at the right time is necessary for their survival.
Don’t move the guppies to the tank until they’re big enough that the other fish won’t eat them. How big they need to depend on the other fish in your tank. It’s usually safe to transfer them when they reach about an inch long but if you have some really big fish, it’s better to wait a bit longer.
Make sure that all of your fish are in good health. You don’t want to introduce a sick guppy that can harm the rest of your fish and vice versa. Look for spots on their fins or sides and make sure they’re all acting normally before introducing the guppies.
Proper preparation is important, too. Makes sure they have plenty of hiding places to make the transition a little easier. The water should be at the same temperature as the breeding tank to help reduce stress.
It’s also a good idea to feed the fish in the community tank before introducing the guppies, just to make sure that none of them are hungry and they don’t see the new tank members as a meal.
Breeding guppies is a really interesting thing to do, especially if you’re a fish lover. Although it can seem overwhelming at first, the process is actually really manageable once you know what you’re doing.
Taking care of the pregnant guppy is an important part of the process. Keep her well fed and as stress-free as possible. Isolating her right before birth in a separate tank or breeding box is ideal but don’t pull her out of the community tank too early.
After the guppy has her fry, it’s important to place her back in the community tank and keep the fry separate or at least give them a lot of places to hide. Fry are very small and the other fish see them as food. Even the mother will eat her own young if left with them after birth.
Taking care of the fry is important, too. In addition to giving them a safe place to hide, feed them well and maintain appropriate water parameters. You can also increase the temperature of the water to 80 degrees F to help them grow a little faster.
Keep in mind that guppies breed often and females can produce fry months after contact with a male. If you have guppies, chances are they’re going to have fry, whether you intend for them to or not. That’s why it’s important to know what to look for and how to prepare for a pregnant guppy.