Royal Pleco Species Profile

Category: Catfish

Common Names: Royal Pleco, Royal Panaque

Scientific Name: Panaque nigrolineatus

Family: Loricariidae

Minimum Tank Size: 120 Gallons

Care Level: Easy

Temperament: Peaceful

Max Size: 16 Inches

Temperature: 72-79 F

pH: 6.5-7.5

Tank Level: Bottom

Colors: Black, Gold

Diet: Omnivore

Breeding: Difficult

Species Overview

The royal pleco (Panaque nigrolineatus) originates from South American waters. In the wild, the royal pleco lives in the Orinoco and Amazon river basins. This tropical fish is popular with aquarists for many reasons.

The royal pleco is a large fish. They are part of the catfish family but have a tropical look. The fish likes to hang out and swim along the bottom and near the sides.

These beautiful fish are not named royal for no reason! This large pleco species has distinct markings of vivid white stripes across a black body. The look of these fish draws much attention from the aquarist world.

The royal pleco is a low-maintenance fish. They do not take much special care, making them perfect fish for beginning aquarists. If you are starting a new tank, check into getting a royal pleco. They get along well with other fish and are easy to care for.

Not all royal pleco fish look the same. A subspecies of the royal pleco family that look similar but have minor physical differences. These subspecies are a great way to get more variance to the look of your fish school.

Distinguishing Features

The royal pleco comes in many color varieties. This variation means you cannot distinguish a royal pleco from another kind of pleco on the color markings. The wide variation makes a royal pleco hard to tell apart from other plecos.

The royal pleco is more massive than most other pleco species. The snow king pleco is the largest fish in the species, but royal plecos are not far behind. If you see a large fish and know it is a pleco, you most likely see a royal pleco.

A giveaway to a royal pleco is the distinct stripes the royal pleco has. The most common color of a royal pleco is vivid white stripes on a black body. Other color variations that a royal pleco might have are yellow-green stripes on black or a light gray body and black stripes.

Royal pleco eyes range from bright red to orange. These brightly-colored eyes sit on a large head. Their downturned sucker mouths indicate that the fish you see is a royal pleco.

Along with their large bodies are large fins. The royal pleco has a large tail fin, adipose fin, dorsal fin, pectoral fin, pelvic fin, and anal fin. Royal plecos fins are large and noticeable, distinguishing them from other fish.

Large Royal Panaque Pleco (panaque nigrolineatus)


Royal plecos are not only found in aquariums across the world but also in the wild! The royal pleco has a wide distribution across South America. This range of habitats shows that the royal pleco adapts to different environments.

The royal pleco lives in rivers across Colombia and Venezuela. Common rivers across this portion of South America include the Arauca River, Spanish Rio Arauca, and the Western tributary of the Orinoco River.

The royal pleco also lives on the lower and middle Amazon and the southern parts of the Amazon basin. These tropical waters stay warm, ranging between 72 to 86 degrees Fahrenheit. This temperature is the ideal temperature for the royal pleco.

The royal pleco likes to live in a rocky substrate. The rocks provide the royal pleco with a place to live and protection from predators and the shining sun. The rocks and caves in their natural habitats provide a good place for females to lay their eggs.

The water of the rivers where the royal pleco resides carries many sediments and rocks. These particles make the water muddy and murky. Plants scatter throughout the water, with plants living in the rainforest surrounding the rivers.

The royal pleco lives in freshwater rivers. The waters can become brackish during certain times of the year because minerals wash through the rivers.

Young Royal Pleco


One of the reasons the royal pleco got the name royal was because of its size. As with anything named royally, the royal pleco is a large fish for the pleco species. They are some of the largest plecos.

Royal plecos typically reach a length between 15 to 24 inches when fully grown. The royal pleco is a large species of pleco. The length of the royal pleco depends on the subspecies of the pleco.

Nutrients also play a role in the size of a full-grown pleco. If the royal pleco is malnourished, it will not grow to its full potential. If you see a full-grown pleco less than 14 inches in length, it is most likely under-nourished.

Male royal plecos are slightly larger than female royal plecos. Males tend to have a larger head than females, but females have a rounder and larger belly than males. During the breeding season, males’ whiskers get much larger than females’ whiskers.

If you see a small pleco, do not assume it is not a royal pleco. Royal plecos take years to reach maturity. A small pleco in an aquarium may be a juvenile royal pleco that has not had time to reach its full size!


If you look for a fish for your children to add to their tanks, you do not want to get a fish that will die in a few months. A long-lasting fish gives children the proper time to bond with and enjoy their fish friends.

A royal pleco is a great choice to get as a gift for an aquarium. A royal pleco expects to live at least ten years. This time gives the fish and the owner enough time to learn things about each other and bond.

When taken care of well, a royal pleco lives up to 20 years! Royal plecos are more expensive than other plecos, but their longevity makes up for the cost! You will not be disappointed with a royal pleco in your aquarium tank.

The better you care for your royal pleco, the longer it will live. A good diet and a clean tank give a royal pleco a chance at outliving many fish in your tank. Proper care will benefit your royal pleco and allow for years of enjoyment. If you take care of them, they will take care of you!

lcamtuf [CC-BY-SA-3.0]


Distinguishing between genders of fish is a difficult task. Without visible sex organs, you have to get creative when determining the gender of a fish. Sometimes they have physical features that give them away, while others have different temperaments between males and females.

Royal plecos have a papilla that sometimes helps when sexing the fish. If the papilla is visible, there are clues to tell what gender the fish is. If the papilla is round and blunt, it is a female. If the papilla is little and pointed, it is a male.

If the papilla is not readily seen, other factors distinguish between male and female. A male royal pleco will have elongated whiskers, especially during the breeding season. The whiskers of the female are not as large and noticeable as those of a male.

Male royal plecos are slightly larger than females. Males have larger heads than females do. The length of a male is longer than a female, but the female’s belly is larger and rounder than the male’s.

If you have a royal pleco that is very aggressive, it is most likely a male. Male royal plecos are aggressive, especially towards other fish. This bad temperament is enhanced during the breeding season.

Large Royal Panaque Pleco


The temperament of a royal pleco varies between fish and the environment. Different environmental factors will trigger a royal pleco to become aggressive. Males and females have different temperaments.

Royal plecos are normally peaceful fish. They tend to stick to themselves at the bottom or sides of the tank. They are typically seen just hanging out in the tank and not causing much trouble between themselves or other species of fish.

If you experience an aggressive royal pleco, a small tank might be the culprit. Royal plecos are territorial fish. If their area gets interfered with, this triggers aggression in the royal pleco and leads to fights with other fish.

Male royal plecos are more aggressive than their female counterparts. During the breeding season, male royal plecos are especially aggressive towards other males that want to mate. Males protect the eggs after the females lay them which brings out more aggression from the male royal plecos.

There can be aggressive females, too. Typically females have a more peaceful temperament, but they can be aggressive in some cases. Females are also territorial, so a small tank can trigger a female to become aggressive.

Royal plecos are most aggressive against their kind. Royal plecos get along with most other fish, but other royal plecos may trigger their aggression.

Tank Parameters

Having the right tank parameters is important to keeping your royal plecos happy and healthy.

Minimum Tank Size

Royal plecos are large aquarium fish. They need large tanks because of their large size. The ideal aquarium for a royal pleco is at least 125 gallons. Larger tanks are preferred.

Thunder Royal Pleco

Water Parameters

The water in the tank is just as important as the tank itself. The salinity, pH, and temperature are all factors that must be considered when you house a royal pleco.


Royal plecos are tropical fish, so they thrive in warmer temperatures. The water should be in the range of 77 to 83 degrees Fahrenheit. The royal pleco is comfortable at this water temperature.


Like most fish, the royal pleco thrives in a mostly-neutral water pH. They can thrive anywhere from 6.5 to 7.5 on the pH scale.


Royal plecos live in freshwater in the wild. Their ideal water is soft, from 2 to 15 dH. They can survive in brackish water, but they prefer fresh water.

Tank Setup

The way the tank is set up will influence the quality of life of the royal pleco. For example, Royal pleco enjoys hiding in large rocks and caves, so giving them ample places to hide will make them feel comfortable and relaxed.


The best substrate for the tank of a royal pleco is rocks. They enjoy medium-sized gravel in the bottom of their tanks.


The best decorations for a royal pleco tank serve more than one purpose. You want decorations that you enjoy the look of but also provide shelter for the royal pleco to live in.


Plants are not required in a royal pleco tank. They do not hurt to put in, but the royal pleco may end up eating the plants.


Royal plecos like low to medium light. They thrive in the rainforest in the wild, so too much light can bother them.


A clean tank is important to the health of a royal pleco. Providing a good filtration system will keep them healthy and free of many diseases.


Royal plecos are tropical fish, which means they need ample heat. Keeping their tanks between 77 and 83 degrees Fahrenheit will provide an adequate amount of heat for the royal pleco.


There is a common myth that royal plecos are herbivores. They are thought to only eat the algae and debris found on the sides and edges of the tank. Royal plecos are not herbivores, but they are omnivores.

An omnivore means that plecos eat both plants and meat. They indeed eat a lot of algae, but plecos also enjoy small crustaceans like mini shrimp. In the wild, they eat small debris of meat and algae.

It is important to provide royal plecos with ample nutrients in a tank setting to keep them healthy. Seventy-five percent of their diet is vegetables, and 25 percent is protein or meat.

Algae-based wafers or flakes are a great way to provide the vegetables needed in the royal plecos diet. In addition, meatier foods like tablets, wafers, pellets, frozen, or flakes are an excellent way to provide the protein the royal pleco needs.

The key to a long life for a royal pleco is providing a varied and balanced diet. A plant-rich diet with low amounts of high-protein foods will result in the healthiest royal pleco.

Royal Pleco


Breeding royal plecos are not recommended in home aquariums. It is a difficult task that is highly unsuccessful in a home aquarium. Multiple factors have to be right for royal pleco breeding to be successful.

In the wild, royal plecos breed during the rainy season. During the rainy season, the water conditions change in favor of breeding royal plecos. These conditions cannot be mimicked in a home aquarium.

The two royal plecos have to bond before breeding. If you only have one male and one female, the two may never bond, leading to unsuccessful breeding. In the wild, royal plecos have more fish to choose from and find a suitable mate to bond with.

In the wild, the more acidic and softer water and slightly decreased water temperature during the rainy are ideal breeding conditions for a royal pleco. The female fish gets plenty of green food and meat and lays her eggs in a cave.

Male royal plecos fertilize the eggs after they are laid. The male royal pleco then guards and protects the eggs. After five to ten days, the eggs hatch. After another three or four days, the fry learns to swim on their own.

Common Diseases

Like any living creature, royal plecos deal with a multitude of diseases and ailments. Knowing these ailments and their symptoms is important in catching them early. If a disease is caught early enough, it may be treatable.

Without the knowledge of common diseases in a royal pleco, your fish can get sick and die. If you want your royal pleco to live its life the happiest and healthiest, become familiar with the following diseases.

  • Ich – Parasitic disease that causes white spots
  • Dropsy – Bacterial disease causing discoloration
  • Fin Rot – Bacterial disease that causes lethargy or loss of appetite
  • Fish Fungus – Fungal growths that look white or grayish on the pleco’s body
  • Pop Eye – Bacterial infection that causes protruding eyes
  • Hole in the Head – An unknown cause that has symptoms of small indentation in the fish’s head

All of these diseases are important to become familiar with. A healthy diet and a good immune system help the royal plecos fight off these bacterial or fungal diseases.

Potential Tank Mates

Royal plecos do well with other fish species but not with other royal plecos or fish in the catfish species. If another pleco is introduced to the tank, it can trigger aggression. Keep this in mind when finding tank mates for your royal pleco.

While royal plecos are aggressive towards their kind, they have a peaceful temperament towards other species. The list of fish below is good candidates for tank mates of a royal pleco.

  • Silver Dollar Fish
  • Headstanders
  • Rummy Nose Tetra
  • Flag Cichlids
  • Congo Tetra
  • Silver Arowana
  • Black Skirt Tetra

If you choose a fish from this list, your royal pleco should do well in a tank with its mates!