Types of Mollies You Can Keep in an Aquarium

Are you wondering how many types of mollies are there? Well, the answer is several.

Mollies come in various body shapes, colors, fin types, etc. If you want to get mollies for your aquarium, you’ll easily find them at your local fish store.

Mollies are one of the most common fish breeds that aquarium enthusiasts like to keep.

The mesmerizing colors and sizes of mollies make them popular. Let’s explore the types of mollies in further detail!

Basic types of Mollies

Mollies are divided into the following two major types:

  • Sail-fin Mollies
  • Short-fin mollies

Let’s learn about each of them further below.

Sail-Fin Mollies

Sail-fin mollies are native to the southern states of the US. They inhabit coastal waters of Texas, North Carolina, and the Mexican Peninsula. Sail-fin mollies also live in fresh, salty, and brackish waters.

The sail-fin mollies are categorized into three distinct species, including Poecilia latipinnate, P. Velifera, and P. Petenensis. P.

Latipinna is very common and native to the US, unlike the other two rare types, which are only available from specialized breeders.

Behaviors of sail-fin mollies

The male sail-fin mollies show peculiar behaviors to attract females. They have a high dorsal with big and beautiful fins. A male molly uses its attractive fins to do an elaborate courting dance.

These colorful fins of male mollies are natural, unlike guppies and other fish that are usually domesticated.

If there are multiple male males competing to get a female’s attention, it’s a sight to see. The dances with their colorful fins make it an extraordinary experience to witness.

In the hopes of getting the attention of a female, male mollies also fight each other. However, no serious damage is done during the process.

There are a few disadvantages to their beautiful fins and flashy dances. In the wild, the mollies sometimes attract predators that can harm or eat them.

As a result, some mollies do not develop a broad dorsal as a survival mechanism. These types of mollies are usually referred to as “sneaky” mollies. They keep a low profile and attract females quietly.

Most of the time, all molly species have a greenish-gray color. When it’s time for courting, the male mollies change their color to a flashy blue, and you can see a golden overcast on its body.

Black markings are also an indicator of a courting molly, but it’s not very common.

Short-Fin Mollies

The short-fin mollies are the second major category of these fish. Unlike sail-fin mollies, this type doesn’t have a high or broad dorsal.

The females of short-fin mollies also have a shorter dorsal fin base.

The short-fin mollies are categorized into several species. The three common types of short-fin mollies include:

  • P. Mexicana
  • P. Latipunctata
  • P. Salvatoris

Domesticated Varieties of Mollies

Apart from the two major types of mollies discussed above, there are a few domesticated varieties as well. Mollies easily hybridize across their categories and give rise to several possibilities.

Many enthusiastic breeders try out different combinations to get their desired results. Mollies have also been cyberized with guppies and other similar fish.

However, their offspring are born sterile, and so it’s not done commercially.

Types of Mollies Based on Color

Mollies are also categorized based on their color. Mollies come in an array of colors and shapes.

Let’s learn about some of their physical characteristics below.


Mollies are sometimes found with blotches on their bodies. These black botches can be natural as well as a result of domestication.

When two black mollies breed together, they often give birth to mollies with black blotches. The quantity and size of these blotches vary from one fish to another.

Gold Mollies

A few mollies sometimes develop scales with red edges. This unusual yet attractive color is referred to as a sunburst.

Sunburst mollies often look golden in the light, and that’s why breeders commonly call them gold mollies.

Silver Mollies

The silver mollies are those fish which eliminate all their pigments except one. Naturally, the mollies form a silver background on their bodies with some shades of green or another color.

When they lose all the pigments, then only the natural silver remains. This gives the mollies a pure silver body, and that’s why they are called silver mollies.


When a molly doesn’t produce any pigment, this phenomenon is called albinism. Albino mollies often appear with a golden-yellowish color. Another characteristic feature of albinos is their pink eyes.

Some albinos also develop bright flecks that display different colors in a different light. These flecks are called iridophores.

This characteristic makes these mollies a remarkable and beautiful anomaly.

24-Carat Gold Mollies

The 24-carat gold mollies are another variety of gold-colored mollies. They usually have short fins. Their golden color is very shiny and bright, unlike the gold mollies mentioned above.

The 24-carat gold mollies have black eyes that are hard to miss with their golden body. This combination of colors gives these mollies a captivating look.

Some 24-carat gold mollies also show a variety of marbling on their bodies. These marbles look very beautiful on their golden and shiny exterior.


Marble spotting is a common occurrence in various types of mollies. These marbles develop regardless of the color of a fish’s body.

Marbling is found on gold mollies, 24-carat gold mollies, and several other skin colors. The number of these marbling blotches vary from fish to fish.

You can’t predict how many marbles will develop on the offspring’s body when two marbled fishes breed together. Marbling on the right skin colors of mollies looks very attractive.

Chocolate Mollies

The mollies who have a brownish or dark-golden color are often referred to as chocolate mollies. There’s no evidence of how this color originated, but you can find this variety commonly.

Some chocolate mollies also have a touch of red on their skin. However, it’s very uncommon. Chocolate mollies are a rarity that you will definitely enjoy keeping in your aquarium.


Mutation is common in mollies because they are cross-bred and hybridized very frequently. Some breeders carefully select a combination and breed the mollies accordingly.

As a result of mutation, there are several types, colors, body shapes, and characteristics of mollies.

Some mollies have short fins, while others have long and bright ones. Breeders also take into account the deformities in the offspring and try to fix stop them by trying other combinations.

The cross-breeding ability of mollies opens doors to several possibilities. Some of them produce beautiful physical features. That’s why mollies are a common ornamental fish in aquariums.

Veil tail Mollies

Veil tail mollies are a variety of this species, which has a wide and large tail. This tail is quite similar to the veil tail guppies. The finnage and color of these veil tail mollies can be variable.

This is because mollies can be bread into any variety, be it color, shape, or finnage.

Balloon Mollies

The balloon molly is a peculiar domesticated variety of molies. This type of molly is usually smaller in size.

They have a distended abdominal cavity in their body. Some aquarists consider these mollies a deformity, but they are usually healthy and safe.

However, you need to ensure that they aren’t put in a tank with aggressive fish. Their abdominal cavity restricts them in their efforts to search for food. So, if they have a competition, they may not last very long.

If you decide to keep a balloon molly, you need to ensure that it gets its meals properly. The balloon trait can also be bred into other mollies.

However, it’s not recommended because these mollies are fragile and require extra care.

Can you Keep Mollies Together?

Mollies usually stick together, so you can keep them in a tank in a tank together. The ideal number would be at least four mollies per tank.

However, you may not want to mix male mollies with female mollies. Male mollies can get aggressive when fighting for the attention of a female.

So, it’s advised to keep either only female mollies in your aquarium or just male mollies.

What Aquarium Size is Suitable for Mollies?

Molly fish need an aquarium with at least 10 gallons of water. This size is appropriate for a maximum of four mollies of regular size.

If you have larger mollies such as the sail-fin molly, then they’ll need at least 30 gallons to thrive. With the addition of each molly after this, you’ll have to add at least 3 gallons to the size of your aquarium.

Final Words

If you’re a new aquarium enthusiast, then a molly would be a wonderful choice for you. Mollies have vibrant colors and shiny fins, which makes them one of the most common ornamental fish in an aquarium.

However, to keep more exotic and wild varieties of molly, you’ll need to be a bit experienced in taking care of fish.

Regardless of the level of expertise, everyone can find the perfect molly for themselves.

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