How to Tell if a Pleco Is Male or Female? 4 Signs to Distinguish

There is no denying that plecos are favorite pets among most aquarists with fairly simple husbandry necessities. However, even professional keepers struggle to determine their gender.

While some species have similar habitat needs, Plecos usually exhibit different gender traits. It means the factors that distinguish females from males in one species may differ significantly in other ones.

How to tell if a pleco is male or female? Let’s find out right now to get the correct answer!

How to Tell if a Pleco Is Male or Female?


How to tell if a pleco is female or male

Here are some of the most obvious signs of whether a pleco is female or male.


There is no denying that size is an essential factor for many animals, including Plecos.

For many species, males are larger than females (in terms of length) and tend to grow faster. However, that is not the case with Plecos.

Female fishes are usually slightly larger than males. However, it’s useless to rely on size if your Pleco fishes are of different ages, especially if you don’t know how aged your fishes are.

So you can only determine the gender of the Plecos if they are the same generation.

Body Shape

Although the difference in body shape may seem insignificant at first glance, females and males have differently shaped bodies.

Generally, males feature more angular, slimmer bodies than females, typically more rounded. You will see this difference when looking at the side of your fish.

Body shape differences will become even more apparent in breeding as the female fish tends to swell with its eggs.


pleco's behavior

Males tend to be more aggressive than females

As for Plecos, males tend to be more aggressive than females. If you have time, observe the behavior of your fish.

Aggressive fish are usually males. Males may fight each other for offspring during the breeding season.

Moreover, male fishes usually claim their cave fast, won’t leave their cave very often, and consider it their territory.

Females will swim around your tank, hiding under many structures or switching hiding spots.


These fishes typically feature odd-looking bristles like many catfish.

The fact is that these bristles typically grow out of the pectoral fin, along their head’s edge, and their mouth.

Both females and males have these bristles for some species, such as Bristlenose Plecos or Bushy Nose Plecos.

In these cases, males will feature more pronounced and larger bristles.

For the species where only male fishes have these bristles, only the male fishes have them, so it’s pretty self-explanatory.

Genital Papilla

It is an apparent sign with many pleco species but is not always as visible.

Male plecos should show a more pointed, longer genital papilla, while the female counterparts show a more round, broader, tubed genital papilla.

Fin Shape

The back fin, or dorsal, is perhaps the simplest method to tell if your Pleco is male or female.

The fins of females tend to be longer and larger. The shape may be different.

Female fishes feature a more rounded, shorter dorsal fin. For males, the back of their dorsal fin should form a point, which would point backward relative to these fishes.


How to tell the age of a pleco?

There is almost no way to determine the age of a Pleco. The only way is to ask its owner or the shop where it is sold.

Pleco’s lifespan typically is between 10 and 15 years, allowing them to outlive most tropical fish.

Of course, there is no guarantee with any fish species when talking about lifespan. Your quality of care will significantly affect your fish’s overall health, for both better and worse.

How Do You Know When Plecos Are Mating?

Like other animals and fishes, Plecos will exhibit some changes during mating.

The males will increase the time they spend near or inside the caves. Meanwhile, the females also begin to spend some time near the cave, more than usual.

One of the obvious signs you may notice is in the male plecos’ breathing. It would increase while they are around the females.

These male fishes will flaunt their fins. The couple would get in a cave, and the male will direct the female toward a selected spawning spot.

Then, the couple will move on to the next face if the female fish approves.

How Many Babies Can Plecos Have?

How Many Babies Can Plecos Have?

A couple can have 150 to 200 eggs at a time

Plecos start to breed once they are one year old.

As we all know, these fishes are prolific breeders. A couple can have 150 to 200 eggs at a time. Also, bigger species can give birth to up to 500 babies.

Do Plecos Eat Their Babies?

The short answer is no! Plecos don’t eat their babies.

But some first-time breeders may eat their babies if there is a severe scarcity of food. But they’ll not decimate their entire fry.

How long can My Pleco Get Full Size?

Your average Plecos may reach the full size in around two years.

Can Multiple Plecos Be Put in A Tank?

When plecos are in one community aquarium, they can thrive, but only if they’re the sole representatives of their species.

Plecos should never live together. The one exception is that you put them in a tank simultaneously when they are babies.

Thanks to that, the plecos are used to being around each other and have never been apart.

The Bottom Line

Determining the gender of Plecos is not as hard as it might seem. Many pleco species show sexual dimorphism, showing visual differences between the sexes.

Hopefully, by now, you should know whether your Pleco is female or male.

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