Platy 101: Care, Diet, Tank Size, Tank Mates & More

The Platy fish (Xiphophorus maculatus), is one of the most popular fish in the hobby for a good reason. These colorful fish are found in many brilliant colors, such as orange, rainbow, and black and white.

The species accepts a wide range of water parameters and is an ideal size and behavior for community tanks.

Platies are often the first fish of many aquarists. In short, they are active animals that like to swim throughout the aquarium and are captivating to care for in a spacious aquarium.

The ideal is that they are kept in a group of at least six individuals so they can feel safer.

This species is incredibly active, and when we mix different colors and patterns, we have a very colorful and fun aquarium.

Rainbow Platy
Rainbow Wag Platy. Image by Marrabbio2

Species Summary

Platy is a species of tropical freshwater livebearer belonging to the Poeciliidae family. These fish are found on the Atlantic coast of North and Central America. From Ciudad Veracruz in Mexico to northern Belize. 

There are feral populations in several countries across the world. The species was accidentally introduced through the release of individuals by inattentive aquarists or by fish that escaped from stores and breeding facilities.

In a natural environment, these Platy are found in channels and ditches with typically slow water flow and small streams and swamps. 

They can also be found in mangroves, lagoons, and pools in the places where they are introduced. They can be found even in environments with poor water quality.

These fish have a specific resistance to salinity, making it possible to find them in environments with a small concentration of salts, such as the mouths of rivers.

Although they are not schooling fish, Platies exhibit gregarious behavior, so they must be kept in groups. A group of colored Platies, randomly swimming around the tank, causes an extraordinary impact on the viewer through a boom of colors.

These fish reproduce very quickly. Because of this, they can become a big problem for aquarists. Depending on their aquarium, it can become overcrowded with many fry.

Platy will readily accept all types of feed, although they prefer flake, freeze-dried, and some types of live foods, such as peanut beetle larvae.

A common species in home aquariums, most specimens available in the aquarium trade are bred in captivity. Wild fish can be extremely challenging to find for sale.  

Some fish keepers and collectors specialize in maintaining and breeding different populations of these fish, being a tiny and closed niche. Some fish can reach a value considered high, even more if we are talking about auctions. Some populations are already extinct in the wild.

Overall, the Platy is a hardy and easy to spawn fish, ideal for beginner aquarists. Also, they enjoy well-planted aquariums with lots of open spaces for swimming.

Platy Care Guide

These fish are very hardy and can live in community aquariums with other fish without problems. Like other livebearers, this species has gregarious habits, so you should always keep it in groups. It is a magnificent species to be kept in a community aquarium.

The Platy is usually a very peaceful animal, making it an excellent fish for community aquariums, but it will also live very well only with others of its species.

Generally speaking, the Platy is ideal for beginners and a great addition to your aquarium. They are active, resistant, and reproduce exceptionally easily in home aquariums. In addition, they are easily found in aquarium stores.

Regarding aquarium water parameters, they tend to accept most of them. However, aquarium water must be clean and within the chemistry and temperature tolerable for the species. Try to add lots of plants to the aquarium of these fish; they will love it!

When well cared for, the Platy is a beautiful fish, but they will show their best colors when given a balanced diet and in a suitable aquarium.

It is a resistant and easy-to-care fish, but that does not exclude the in-depth species, habits, and behaviors. Like any other species, this fish has its peculiarities, addressed and detailed in the following topics.

Tank Size

Although these fish species do not reach a large size, it is highly active and must be kept in a group, hence the need for an aquarium with reasonable space. 

Therefore, they should inhabit aquariums over 21 gallons, with dimensions starting at 31″ x 11″ x 15″. This size accommodates a small group well, always remembering that the more space available, the better the welfare and development of the fish.

Tank Mates

They are peaceful fish and coexist without problems with other animals; they can live with countless other fish species in a community aquarium. This species is friendly and gets along incredibly well with other fish.

Avoid aggressive and larger species that could injure the Platy or that will compete directly for food. Even though they can be kept with fragile and smaller fish, it is best to keep them with fish of similar size and behavior.

Although very rare, this species may bite fish with very flashy and exuberant ends, such as Bettas and Guppies; in this case, avoid using fish with these characteristics.

Caution, this species can hybridize with other livebearer species.

Corydoras, Zebras Pleco, Tigers Pleco, Bristlenose Pleco, Cherry Barbs, Zebra Danio, Guppies, hard water Tetras, and other small livebearers like Endlers make great tank mates.

Same Species Tanks

The Platy is often kept as a single species in large aquariums, planted tanks, or biotope-type aquariums where the species’ original location is mimicked.

It is a great species to be kept alone in a well-decorated aquarium. A group forms many beautiful movements and a beautiful color bright tone contrast.

Water Parameters

They are incredibly resistant fish, which support a wide range of parameters. This species can be susceptible to pollutants in the water, the accumulation of organic matter in the tank, and very acid and soft water.

The perfect temperature for keeping the Platy in an aquarium is 64 to 82 F. The ideal pH range is between 7.0 to 8.2, and hardness is 10 – 30.

It is a great fish option for beginner aquarists due to its rusticity.

This difference between hardness and pH is related to the region of origin of the specimen and demonstrates the oscillation of parameters during the dry and rainy seasons.

What to Put in Their Tank

As for any other aquatic animal, an aquarium heater and a filtering system are essential to keep the tank with Platy healthy. The filtration system must be well-sized, creating a low water flow. 

Given the rusticity of the species, it can inhabit different aesthetic styles, from Amazonian themes to Asian and African ones, if it tends to the alkaline side. 

Even though aquarium decor is not critical to ensuring successful maintenance of the species, it is incredibly beneficial to have a tank that mimics the conditions of its biotope.

Densely planted aquariums with decorations such as driftwood and rocks provide shelter for the fish and their fry. It also provides a place for females to hide from male’s harassment.

These fish do well in well-lit environments and slightly shaded environments. They are indifferent to the substrate, make sure the tank is well decorated, and forms hiding places and territories.

As densely planted as the fish tank is, you should leave an open space for them to swim freely.

Avoid keeping the species in a blackwater aquarium (with dark water due to the presence of tannins). As much as these fish may come to inhabit dark waters, the concentration of acids in aquariums may unbalance the number of salts present in the water.

In the same way, avoid using salt in the water of your Platy aquarium; if you need to increase the hardness or pH, make use of substrates, rocks, and products suitable for this use in aquariums.

Common Diseases

Like most hard and alkaline water fish, this fish is highly prone to acidosis.

This condition is seen when the pH or hardness of the aquarium water is below the ideal range required by the species in question. This disease does not necessarily affect all aquarium inhabitants because fish of different species differ from each other in the field of pH values that are acceptable to them.

Like symptoms, the fish can lose mobility, and appetite, increase mucous secretion, and its gills can change color. Hemoglobin can be affected, causing the animal not to breathe correctly and become disoriented, gaping at the surface, or, if the change is too extreme, causing its death.

In more advanced cases, the fish may have corrupted ends of the fins, white spots on the body, closed fins, lack of appetite, and stress.

This condition can be acute (when it occurs because of a sudden change) or chronic (when the change happens over time). Carrying out weekly tests of this parameter will be essential to have a balanced aquatic ecosystem.

They are remarkably disease-resistant fish. Keeping the quality of the water and the tank always in optimal conditions and a good quality diet, your fish should not present any problem. Remember to always quarantine new fish before placing them in the main aquarium.

Food and Diet

This species, like other livebearers, is omnivorous, feeding on anything that will fit in its mouth.

In the wild, the Platy’s primary diet is various foods, including worms, plant matter, crustaceans and insects. Its consumption will depend on the availability of food in the natural habitat. In an aquarium, these fish readily accept all types of food.

A good combination of using a high-quality commercial feed and live, fresh or frozen foods such as brine shrimp or daphnia, with fresh or bleached vegetables like zucchini and cucumber will make these fish look much more vivid and their behavior closer to natural.

Set a time to feed the fish, always trying to give an amount that can be consumed quickly. They are fish that are always hungry. Try to feed your fish a varied, high-quality diet. Providing a diverse and balanced diet is essential for the species to demonstrate its full potential.

Lifespan

In an aquarium with all the correct parameters kept stable and with an ideal diet, this animal can live for around four years, the most common being around three years.

In nature, these animals are prone to live less, as they are predisposed to diseases, attacks from other animals, and environmental causes.

Appearance

Wild Platies are very different in color than their aquarium cousins, displaying a dull gray color typical of wild fish. Its body can present spots, forming a specific pattern on the animal’s body.

Males ready to mate undergo a slight color change and may show a slightly reddish tone.

It has several varieties with different colors and body conformations as an ornamental fish, giving rise to subdivisions such as the Balloon, Tuxedo, and the Lyretail.

While there are numerous varieties of color and shape of this fish, most strains have a similar body shape and style to the typical Platy.

These fish have the classic shape of livebearers. A stout, laterally flattened body with a thick tail section, in symmetry with its height and a triangle-shaped head with a pointed mouth. The ends of its fins are rounded, and the dorsal fin tip is high and angled.

Its body structure is presented as being wider precisely in the middle of the animal, tapering towards the ends.

Several varieties are found in captivity, such as Mickey Mouse, Wagtail, Smoking, Moon, Blue, Red, Comet, and Hi-fin. There are also several subspecies in its natural environment. Some are still to be classified, presenting different colors than the varieties obtained in captivity, such as olive green, white, and black with bluish fins.

Size

A Platy Fish can quickly grow to 3 inches in length when well cared for and fed. Being the everyday sight around 2 inches.

Behavior and Temperament

It is a tropical fish species with peaceful behavior with individuals of other species as well as those of the same species, and can be kept in a community aquarium with fish of the same size and behavior. 

They are very active animals, occupying practically all strata of the tank; however, they prefer to feed on the surface. 

The fish behavior is more natural when kept in a group of at least three individuals. If you keep in pairs or trios, there may be persecution of the weakest of the group. In the breeding season males can become aggressive with each other or when placed in a tight space. 

The males develop a distinct hierarchy because of this, these fish can be aggressive with each other when a more significant number of males is introduced. Because of this, you must maintain the ratio of two or three females to each male.

Their behavior can change if they don’t feel comfortable in the tank hidden among vegetation, rocks, and driftwood. 

While not necessarily aggressive to other fish species, some Platies can occasionally nibble on slow-moving or long-finned fish. This behavior is more evident when space is limited or the fish are under stress.

Breeding

Captive breeding is very easy and is carried out commercially and even accidentally in home aquariums worldwide.

It is an ovoviviparous species, where the male must internally fertilize the female. The eggs develop inside the mother until they hatch, and the fully developed offspring are born. The female simply disperses the fry somewhere in the water column.

The female can store the male’s sperm for a long time, using the same for her subsequent pregnancies. The gestation period varies between 24 to 30 days, and the female produces from 20 to 200 larvae. The number of eggs is directly related to their age and physical condition; younger females tend to produce less.

The male will then fertilize the female, where the larvae will hatch in about 28 days. During this period, they develop internally in the female, and when expelled, they are born formed and swimming freely; spawning duration can range from two to more than ten hours. 

The interval between the first births can be irregular and between 27 and 90 days.

The species exhibit no parental care. They are incredibly prolific and reproduce quickly.

Throughout the gestation period, the Platy will show several behavioral changes. The behavior change will begin right before the courtship and increase as approaches the birth of the fry.

The most unmistakable sign in the female is the gravitic spot, a black spot near the anal fin. This spot gets darker as the female gets closer to giving birth.

Also, when they are close to giving birth, the females hide in different places in the aquarium, avoiding contact with other fish. Ensure there are good decorations and plants so the females and the fry can hide them during this time.

If you want to raise the fingerlings, you can separate the female in another aquarium and wait for the spawn. However, females can eat fry. Because of this, there are different types of incubators to separate the fry from the mother.

They are easily reproduced fish, where spontaneous reproduction can occur in any domestic aquarium, as long as it is well taken care of.

Gender Differences: Male vs. Female

There is apparent sexual dimorphism in adult animals. Adult males are smaller and more colorful than the females and have an adapted anal fin in the form of a gonopodium (anal fin adapted for reproduction, in the shape of a stick). 

Females are larger, more robust, and do not have a gonopodium; instead, there is a typical anal fin.

Platy Fun Facts

A prevalent species in home aquariums, there are several domestic strains, rarely finding a pure variety (f1). We even found traces of genetic material from other species of the genus, namely crosses between Xiphophorus variatus and Xiphophorus hellerii.

Its scientific name, Xiphophorus, derives from the Greek ksíphos, which means “a kind of double-edged sword”, and phóros, which means “bearing,” in allusion to the presence of a gonopodium in males of the genus. The epithet maculatus, comes from the Latin spotted a reference to the abdominal point.

References

McKay, R.J., 1984. Introduction of exotic fishes in Australia. p. 177-199. In Courtenay, W.R. Jr. and J.R. Stauffer, Jr. (Editors). Distribution, Biology and Management of Exotic fishes. The John Hopkins University Press, Baltimore, Maryland, USA.

Rodriguez, C.M., 1997. Phylogenetic analysis of the tribe Poeciliini (Cyprinodontiformes: Poeciliidae). Copeia 1997(4):663-679.

Schliewen, U.K., 1992. Aquarium fish. Barron’s Education Series, Incorporated. 159 p.

Yamamoto, M.N. and A.W. Tagawa, 2000. Hawai’i’s native and exotic freshwater animals. Mutual Publishing, Honolulu, Hawaii. 200 p.