Are Mollies Schooling Fish?

Mollies are not schooling fish. The number of males in one tank is typically less than the number of females. However, when they keep chasing all the females in what seems like a uniform, unidirectional movement, people get the misconception of them being schooling fish.

Many pet owners believe that Mollies are schooling fish. Many others disagree. But what’s the truth? Are Mollies schooling fish?

To get more into the heart of the matter, we need to understand the difference between schooling fish and shoaling fish.

Group of White Mollies

Are Mollies Schooling Fish?

Mollies aren’t schooling fish, but their movement together to reproduce could be mistaken for schooling. In fact, mollies are more shoaling than schooling fish.

It’s common to mix up between schooling fish and shoaling ones since both of them are similar fish behaviors. But they’re still somewhat different from each other.

Schooling is when a group of fish moves at the same speed, in the same direction, and simultaneously. The schooling groups could be made of more than one species, but they usually have only one type of fish.

Shoaling is when a group of fish swim together in loose groups. They usually have different speeds and species, and it’s not uncommon for a few fish to break off the swarm.

Many pet owners believe that Mollies are schooling fish, but they’re not. However, there’s a reason why some people think so.

Why Do Mollies Seem Like Schooling Fish?

Mollies seem like schooling fish because they give the illusion of moving together on many occasions. Mollies are often kept in groups, and the males usually keep following females, which causes people to get mistaken.

Generally, Mollies are best kept in groups of four, with a ratio of three females to one male.

If you keep a group of four Mollies together, they will reproduce, or at least try to. This is why you often find them swimming together and in the same direction, which gives the illusion of schooling.

In this scenario, the fish swimming aren’t schooling; they’re probably trying to mate for reproduction. Since there’s only one male in that group of four, he will follow all the females most of the time, adding to the illusion of schooling.

If you keep more males than females or a group of all-male Mollies, the schooling behavior would be noticeably less.

You could keep more males if you want. However, we don’t recommend that.

Why Shouldn’t You Keep More Males Than Females?

As a rule of thumb, you should keep the ratio of the tank as one male to three females. If you keep male mollies alone in the tank, they’ll get aggressive during mating times.

Additionally, if you reverse the ratio, say three males and one female, this could be problematic. It needs a bit of a background explanation, so bear with us for a minute.

Mollies are live-bearing fish, which means that the females keep their eggs inside them until they hatch. As a result, this gives the illusion that they give birth to live fish, hence the naming.

The whole process is more stressful for the females than laying eggs. Some Molly females pass away after giving birth due to strain and complications. Giving birth is already hard as it is; waiting for the eggs to hatch inside makes the process even harder.

The courtship between male and female Mollies adds up to the stress even more. Even if the female is pregnant, males would still harass her.

This is why you should always keep more female Mollies than males. And this is also why male Mollies follow the females constantly in what looks like schooling.

So now we know that Mollies are not schooling fish, but does that mean we can’t keep them with other fish?

Can Mollies Live With Other Fish?

Except for the occasional aggression that happens during mating times, Mollies are peaceful fish with no problem staying with other fish.

However, choosing smaller fish is preferable so they don’t bully your mollies.

Good candidates for Molly’s companions are Keyhole Cichlids, Rams, and Discus Fish. Yet, the best Molly companions remain -you guessed it- other Mollies.

But what if you decide to keep one molly? Is that okay?

Reasons Some Mollies Should Stay Alone

You “can” keep one Molly on her own, but she can get lonely, especially if you don’t interact with her much.

However, there are several reasons you might want to keep a Molly fish alone.

Reason 1: To Prevent Reproduction

If you don’t want your Molly to reproduce, you could keep her on her own. But you’ll need to provide her with good stimulation, good food, and keep the tank clean at all times.

You could also resort to the solution of keeping two Mollies of the same gender. Then, you’ll solve the loneliness issue without getting unwanted baby Mollies.

Reason 2: Diseases

If your Molly has any disease, it’s best to keep her away from her tank companions until she gets better.

A sick Molly will easily be harmed and bullied by other tank mates, and it could be fatal.

Reason 3: To Prevent Bullying

Is your Molly often taking a beating from her tank mates? Keep her in a separate tank for her own good.

You could keep both tanks close to each other to prevent your separated Molly from getting bullied.

If your Molly is the bully, keep her temporarily away from her mates. You could try to re-introduce her to the tank again to see if she would stop bullying.

In most cases, the reunion will be peaceful. However, if the bullying continues, keep her permanently in a separate tank.

Again, keep the tanks close together to avoid loneliness.

That’s a Wrap

The difference between schooling and shoaling isn’t that big. Many people don’t understand that difference. In most cases, they only mean that Mollies swim in groups.

That’s not wrong. Mollies like to swim in groups, but their swimming pattern doesn’t fall under the schooling fish category.