Why Do Mollies Change Color?

Last Updated on June 28, 2022 by cmoarz

There’s nothing worse than picking out the perfect molly only to have it change color a few weeks later. So, what’s the deal with mollies and their chameleon-like tendencies?

Mollies are known for their ability to change color. In fact, it’s not uncommon for a molly to go from one extreme of the color spectrum to the other. For example, a black molly may turn white, or a yellow molly may turn red.

This can be really frustrating for fishkeepers, especially those who are new to the hobby.

So, why do mollies change color?

There are a few reasons why mollies change color. The most common reason is due to stress. Stress can be caused by a number of factors, including:

Morkie Color Changes
Morkie Color Changes

-Poor water quality

-Lack of hiding places

-Incompatible tankmates

-Not enough food

But color changing isn’t always a result of stress, mollies have a lot of other reasons to change color.

These include the food they eat, the color of their environment (much like a chameleon, although to a less extent), Sickness, or infection.

Mollies may also change color as they reach maturity and become ready to breed. For example, a male molly that is ready to breed may develop bright colors to attract a mate. Once the molly has found a mate and spawned, the color may fade again.

Color changing in mollies can also be hormonal. Female mollies that are getting ready to give birth often develop dark spots on their bodies. These spots are called gravid spots and they help the female molly to release her eggs when she is ready to spawn.

Males mollies may also develop dark spots, but these are usually not as pronounced as the gravid spots on females.

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Genetic predisosistion

Sometimes mollie will change colors purely because of their genes. Sometimes more dominant genes will kick in, especially with age. For example, a molly that is mostly black may gradually start to develop more and more white spots as it gets older.

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Is there anything you can do to prevent it?

You may be wondering if you can stop a molly from changing its color. Unfortunately, there’s not much you can do to prevent it.

The best thing you can do is try to provide your molly with the best possible conditions.

This means regular water changes, a good diet, and compatible tankmates. If you can do this, then you’ll help to reduce the amount of stress in your molly’s life, and this will help to prevent color changing.

You should also be aware that some color changes are inevitable. For example, most mollies will change color when they reach maturity and become ready to breed. This is a natural process and there’s nothing you can do to stop it.

Keep these things in mind when you are buying your mollies. Some breeds are more prone to color changes than others, And sometimes you can even guess what colors a molly may turn based on its current color.

It may take some research but it’s always worth it!

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Bottom line

Mollies change color for a variety of reasons, the most common being stress. However, color changes can also be due to factors such as diet, environment, and genetics. There’s not much you can do to prevent color changes, but you can try to provide your molly with the best possible conditions to reduce stress.


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