Can Guppies Breed With Platies? Will They Crossbreed?

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So many times, I’ve been asking myself whether guppies can breed with platies. Sometimes I saw little fry in a tank that contained both species. For that reason, I used to believe that crossbreeding is possible. However, over the years, I’ve learned why I was mistaken. Now, I am willing to share all the lessons I’ve learned.

Guppies cannot crossbreed with Platies because they come from different families; Poeciliidae and Xiphophorus, respectively. However, fish can breed with different species within their genus. For that reason, Guppies can crossbreed with Mollies and Endlers, while Platies can breed with Swordtails.

As we move forward, I will explain why so many aquarists believe that guppies and platies can crossbreed. Also, I’ll elaborate on the mysterious case in which a female platy or guppy fish becomes pregnant in the presence of a male from a different genus.

Also Read: Breeding Guppy Fish

Do Guppies Breed With Platies?

Crossbreeding is reasonably common among aquarists, especially those who want to produce more attractive ordinary fish versions. Certainly, guppies and platies are quite popular among crossbreeding circles.

Some people have argued that the question of Guppy/Platy crossbreeding is still open. That is to say; they believe that it is still unclear as to whether or not you can breed the two species. But such doubts are only held by laypeople. Scientists and experienced aquarists hold a firm stance on the issue.

The general opinion suggests that people crossbreed guppies and platies all the time, in which cases, there is no reason to wonder whether guppies can breed with platies. However, it would help if you weren’t so quick to jump to that conclusion:

What Some Aquarists Say

A conversation with multiple aquarists will convince you that crossbreeding between guppies and platies is possible. Some of them will reject this notion altogether. But if you were to base your opinion solely on aquarists’ feedback, you might walk away convinced that crossbreeding between the species is possible.

Not only do a significant portion of aquarists support the idea, but a few of them will argue that they have successfully produced guppy/platy hybrids. Some of these aquarists will go so far as to present visual evidence (images and videos) of the fry produced in their tank after their guppies and platies mated:

Scientists have refuted some of this evidence. However, that hasn’t stopped aquarists from claiming that crossbreeding between guppies and platies is possible. This debate is by no means settled. If you were to plunge into the conversations raging among aquarists on this issue, you are unlikely to receive any clarity. The fish-rearing community hasn’t yet reached a consensus.

What Science Says

Scientists and scholars don’t have any doubts here. As far as they are concerned, guppies and platies cannot crossbreed.^[1] Can guppies and platies mate? Yes, they can. As I’ll demonstrate later, both species are quite enthusiastic where mating is concerned.

A male guppy will happily chase and mate with a female platyfish. Guppies don’t discriminate in this area. All they care about is reproducing. Because both species are livebearers, mating is necessary for reproduction to occur.

A male fish’s sperm must fertilize the eggs in a female fish’s body. While guppies and platies can mate, the guppy won’t impregnate the female platy, and neither will the platy produce fry.

Scientists argue that guppies and platies are incompatible because they come from different families. Guppies come from the Poecilia Reticulata family, while Platies come from the Xiphophorus Maculatus family. Fish can crossbreed with other species within the same family. However, they cannot crossbreed with species from a different family.

The divide between guppies and platies is too great. Those people who made a concerted effort to crossbreed the fish say that their platies eventually produced fry with deformities that died quickly. They also recorded stillbirths.

Why do People Try to Crossbreed Guppies and Platies?

People experiment with crossbreeding between guppies and platies because they share so many attributes. Since they are quite alike, they can co-exist peacefully in the same tank. These attributes typically lead aquarists to think that the two can crossbreed:

Both species’ temperaments are mild.
Platies are slightly larger than guppies, but that won’t stop the species from sharing a 20-gallon tank.

Their pH, hardness, and temperature requirements fall within the same range.
They both require filters, heaters, regular water changes, and ample foliage.
You can also feed them with a similar diet since both species are omnivorous. In other words, they are not incredibly picky where their food is concerned.

The most attractive aspect of both species is their breeding habits. As I mentioned earlier, it doesn’t take much to breed guppies or platies. So long as you have both genders in a tank, guppies, and platies will multiply with relative ease, especially if you make every effort to protect their young (both species have a reputation for eating their fry).

Any attempt to crossbreed guppies and platies wouldn’t require much effort. They get along so well that confining the fish to the same tank is all it would take to encourage mating between the species. Yet, as was noted above, the two species cannot impregnate one another.

Why are Some Convinced they have Successfully Crossbred Guppies & Platies?

People who claim that their guppies and platies are mated to produce healthy hybrids are not necessarily lying. They are simply mistaken. If you are new to guppies and platies, the notion of an aquarist mistaking ordinary breeding between platies and guppies sounds ridiculous.

But it makes sense once you realize that female platies can store sperm. People think that crossbreeding between the two species happened because they added a female platyfish to a tank with a male guppy, and then, a few weeks later, they saw fry.

They concluded that the male guppy and female platy must have mated to produce the hybrid fry based on that observation. After all, the female platyfish had no male platies to mate with. With the male guppy as its only plausible mating partner, they are forced to conclude that the two crossbred.

However, because platies can store sperm, they can give birth to healthy fry in the absence of a male platyfish. If you bought your platyfish from a store, it most likely acquired sperm from a male platyfish before you took it home.^[2]

Females can use that sperm to give birth to fry on multiple occasions. In other words, those healthy fry in the tank are not a guppy/platy hybrid. They are merely the young of your female platy. Female guppies can do the same thing; they can store sperm for long periods.

An aquarist who is unaware of this attribute and who saw their male guppy chase and mate with the female guppy will naturally conclude that any new fry in the tank results from crossbreeding. Mollies are sometimes pulled into these discussions.

Like guppies, mollies are livebearers that share a lot of attributes with platies.^[3] Also, the fish are friendly towards one another and appreciate the same parameters in the tank. Therefore, many people are tempted to crossbreed them.^[4]

But, like guppies, Mollies come from the Poecilia family. They cannot cross the divide to breed with a Xiphophorus fish like the platy. As a rule of thumb, you should remember that different species can rarely crossbreed.

What Fish Can Breed With Platies?

Platies can breed with fish inside the Xiphophorus genus, including different species of platyfish, such as the Spiketail and Monterrey. Swordtails also belong to the Xiphophorus genus and, therefore, can crossbreed with platies. That is in contrast to mollies that are part of the Poecilia genus.

The Xiphophorus genus consists of fish from North Central America as well as Mexico.^[5] Generally, platies can crossbreed with other fish within this family. They are particularly compatible with swordtails, a species that belongs to the Xiphophorus Helleri family.

Platies and swordtails get along. They also share many attributes, which allows them to thrive in tanks with the same parameters. Yet, platies and swordtails rarely crossbreed in the wild. Or at the very least, their hybrids are rare in the wild.^[6] However, in aquariums, they breed quickly and enthusiastically. Their offspring have traits of both species.

What Fish Can Crossbreed with Guppies?

Guppies can crossbreed with Mollies and Endlers since all three species are Poeciliidae, a family of fish from Africa, Southeast US, and Argentina. Given the proper water conditions, including a temperature of 72-78 ºF and a pH between 7.5-8.5, these species will easily crossbreed.

Nevertheless, it would be best not to expect every attempt at crossbreeding to succeed. Mating between mollies and fancy guppies, for instance, has been known to produce unviable fry. Endler guppies are in a similar boat. You can try crossbreeding them with fancy guppies.

However, the fry that emerges from this mix tends to manifest genetic mutations that will considerably reduce their lifespan. Even if they survive, they are more vulnerable to disease. That can make them a nightmare to care for.

A cross between mollies and guppies is far better. With the right conditions, the chances of producing healthy fry are decent. Though, don’t expect those fry to produce more fish when they mature. Molly/Guppy hybrids are infertile and cannot reproduce.

As you can see, crossbreeding of any kind is associated with a variety of risks. Even among fish from the same family, you cannot guarantee that crossbreeding will produce viable fry. Fortunately, guppies and platies are voracious breeders.

The male fish, in particular, are so passionate about reproducing that they will hound their female counterparts to the point of stressing and possibly even killing them. This gives you plenty of opportunities to experiment.

Given enough time, you are bound to produce some health fry from couples within the same family. But it would help if you didn’t let anyone trick you into believing that a guppy and a platyfish can crossbreed.

If you observe the healthy fry in a tank with one female platy and one male guppy, you will realize that the fry bears a strong resemblance to the platyfish. Female platyfish can use the stored sperm to fertilize the eggs and produce fry several times in a tank that doesn’t have a male platyfish.

Conclusions

Guppies and platies cannot crossbreed since they don’t come from the same family. If you’ve witnessed a pregnant guppy or platy giving birth, bear in mind that the sperm didn’t come from the other species.

Since guppies and platies can store sperm, the females may hold the male’s contribution from their previous tank. For example, it could be that the male had released its sperm back in the pet shop, but only a few weeks after the female got pregnant.

If you wish to crossbreed guppies or platies with other species, you should pick those that belong to their genus. You can quickly breed platies with swordtails, for that matter, or guppies with mollies and Endlers. But if the two species do not share the same family, it is impossible to crossbreed them.