The royal pleco is one of the most unique-looking fish. Owing to its earthy color and inactive nature, most people hardly notice its presence initially. However, its intimidating appearance adds the WOW factor and often becomes a head-turner for big community tanks.
It is much bigger than most catfish and easy to care for. So, if you plan to get one, let’s dig in!
Species Overview
| Origin | Orinoco River and some tributaries of the Amazon River, South America |
| Order | Siluriformes |
| Family | Loricariidae |
| Scientific Name | Panaque nigrolineatus |
| L Number | L190 |
| Common Names | Royal pleco, royal plec, royal panaque, royal catfish, panaque |
| IUCN Red List Status | Not Evaluated |
| Appearance | Brown to grey color, longitudinal indefinite stripes, red eyes, catfish-like shape |
| Size | Up to 43.0 cm (16.93 in) |
| Lifespan | Up to 10 years |
| Temperament | Slightly aggressive towards own and similarly big species; Peaceful with non-territorial small species |
| Tank Level | Bottom dwellers |
| Water Temperature | 70-86 °F (21-30 °C) |
| pH Level | 6.5-7.5 |
| Water Hardness | 5-15 dGH |
| Care Level | Moderate |
| Minimum Tank Size | 125 gallons for one |
| Tank Environment | Spacious, soft substrate, void of plastic or small stones, high water flow. |
| Diet | Omnivorous, primarily herbivorous |
| Tank Mates | Other smaller, peaceful, non-territorial, and non-fin-nipper species. |
Classification
In the aquarium trade, several notable Panaque species are called “royal plecos”. They might be type species, subspecies, or even color morphs. The “Panaque” is a common Venezuelan name for all of them.
All of them have been identified owing to their varying natural habitat, environmental conditions, physical appearance, and other details.
The most common features that bring all the species together are their unique spoon-shaped teeth which have a wide tip and become narrow near the roots. They also lack a flap of skin called buccal papillae.
These species are also avid wood and vegetable eaters. So, despite the difference in their origins, they are often spotted near fallen trees and tangled wood on streams, rivers, and tributaries.
However, this think-piece talks about Panaque nigrolineatus, a type species of the Panaque genus.
So, while the rest of the article will revolve around the Panaque nigrolineatus, let’s quickly skim through the other types!
Popular Royal Pleco Types
Currently, seven valid species under the Panaque genus have been identified. In the future, there is a high chance that this number will only grow. But here, we will learn about the most popular species and their subspecies!
Watermelon Royal Pleco (Panaque nigrolineatus laurafabiane)
- Natural Habitat: Orinoco River, Guaviare River, lower and southern middle tributaries of Amazon River.
- L Number: L330
- Size: 43.0 cm (16.9 in) or more
- Temperament: Peaceful but territorial around conspecifics
It looks exactly like the Panaque nigrolineatus other than its spotted body instead of stripes. The adult fish might have some stripes along with some spots.
It also has orange or red, and two corners of the tail fin have bright orange coloration. You can also notice a faint orange on the border of its fins.
Blue-eyed Royal Pleco (Panaque cochliodon)
- Natural Habitat: Magdalena, Cauca, Caribbean Rivers, Colombia, South America
- IUCN Red List Status: Near Threatened, 2014 assessment
- Size: Up to 40.0 cm (15.7 in)
- Lifespan: Up to 10 years
- Temperament: Peaceful but territorial around conspecifics
It has the standard spoon-like teeth and absent buccal papillae like all panaque species. Besides that, it has bright blue eyes, as its name says. Its body is grey or greenish-grey.
A healthy specimen won’t have a sunken belly or sunken eyes.
Broken Line Royal Pleco (Panaque sp.)
- Natural Habitat: Amazon, Solimoes (middle Amazon), Japura, Caguan, Caqueta, and Upper Caqueta Rivers
- L-number: L191
- Other Common Names: Dull Eyed Royal Pleco or Green Panaque
- Size: Up to 50.0 cm (19.7 in)
- Lifespan: More than 20 years, (if cared for properly)
- Temperament: Peaceful but territorial around conspecifics
Other than the typical physical characteristics of a pleco, this one has dull-colored eyes and not bright red, orange, or blue ones. It has an olive body that becomes grey as it ages.
Both the young and adult fish has black horizontal stripes all over its body. The young fish, however, has a clear caudal fin, a white ring around its caudal peduncle, and white tips on its fins.
Tapajos Royal Pleco (Panaque armbrusteri)
- Natural Habitat: Tapajos River, lower Amazon basins, Brazil, South America
- IUCN Red List Status: Least Concern, 2018 assessment
- L Number: L027
- Other Common Names: Thunder Royal Pleco
- Size: Up to 40.0 cm (15.7 in)
- Lifespan: Up to 10-12 years
- Temperament: Peaceful but territorial around conspecifics
The base body color and eye color of this pleco are golden beige. The fish is also called Thunder Royal Pleco because of the light colors in between the stripes and the sounds it makes.
It has black or dark brown stripes all over it. The young fish has a clear stripe on its dark brown or black caudal fins. The caudal fins don’t have posterior edge color. Its caudal fin is also truncate. On the other hand, the adult fish’s teeth are angled at 100° or more.
Xingu Royal Pleco (Panaque cf. armbrusteri ‘xingu’)
- Natural Habitat: Xingu River, lower Amazon basins, Brazil, South America
- L Number: L027 ‘Xingu’ or L027A or LDA063
- Other Common Names: Longnosed Royal Pleco and Red Fin Royal Pleco
- Size: Up to 40.0 cm (15.7 in)
- Temperament: Peaceful but territorial around conspecifics
The young fish has multiple rusty patches on its caudal fins. The caudal fin is almost translucent other than the black marble-like shading on the posterior side. It has rusty red eyes.
The adult fish looks almost black and has dark or bottle-green stripes. For species with this body size it has the largest fins. Its unpaired fins are in black, but the dorsal fin rays are dark green.
Platinum Royal Pleco (Panaque cf. armbrusteri ‘tocantins’)
- Other Common Names: Tocantins Royal Pleco
- Natural Habitat: Tocantins River, Brazil. lower Amazon basins, South America
- Size: Up to 40.0 cm (15.7 in)
- Temperament: Peaceful but territorial around conspecifics
The juvenile fish has a light base body color with black horizontal stripes. Its caudal fin rays are single-colored, and the tail is entirely black.
As it grows, the fish body darkens to a medium to dark green base color, and the black stripes persist. It has orange eyes.
Goldline Royal Pleco (Panaque cf. armbrusteri ‘araguaia’)
- Natural Habitat: Tocantins River, lower Tocantins, Araguaia River, Amazon basins
- Other Common Names: Rio Araguaia Royal Pleco
- Size: Up to 40.0 cm (15.7 in)
- Temperament: Peaceful but territorial around conspecifics
The fish has a yellowish-green body with black or dark brown horizontal stripes. The corners of the tail fin are orange, and its eyes are brownish-red with a hint of blue or purple.
Royal Pleco (Panaque nigrolineatus) Natural Habitat
The fish is naturally found in South America’s Orinoco River and the lower and southern middle tributaries of the Amazon River and in the nations: Brazil, Columbia, Venezuela, and Ecuador.
It mainly inhabits near huge roots and rocks, for example, near the river banks, to seek shelter when in danger.
It’s often spotted in shallow yet fast-moving streams and rivers and hides in acidic black waters.
Fun Fact: The fish is an avid algae eater. It will scrape away any algae growth with its strong rasping teeth and keep your tank clean.
Appearance
The body of the fish, though huge and unconventionally shaped, it still resembles a catfish. But let’s understand its appearance better here!
Size
The standard length of the average adult royal pleco is about 43.0 cm (17.0 in).
Color
The base color of the fish is muted grey to brown. It has laterally running bold dark brown or black stripes all over it. These stripes are not the same in every fish, which makes them unique.
It has red to bright orange eyes and its dorsal fin tip has a creamy gold shade.
Features
The fish has a distinguishably large head with a sucker mouth on the bottom side. Compared to most other armored catfish, most of its mass is placed in the head. It makes the head thicker and the fish stronger and taller than the rest.
It has a large mouth and sharp spoon-like teeth, which help it scrape away and eat fungi, algae, and wood.
The fish has an expansive dorsal fin and lacks scales. Instead, its entire body is shielded with armor-like skin plates, which are pretty soft around its belly.
Sexual Dimorphism
Young royal plecos can’t be sexually differentiated by any means. You must wait till they are adults to check the vents on their underside.
The female fish has a rounded and blunt genital papilla and the male fish has a small, pointed genital papilla.
Behavior & Temperament
This is a nocturnal fish and a bottom-dweller, so you won’t see it moving around throughout the day.
It will rest on the aquarium bottom and pay no heed to other tank mates in different tank levels. In other words, the fish is particularly indifferent to other smaller and docile species.
However, it turns aggressive and steals the territory or food of other species when it is starved.
In the presence of another pleco or catfish, it becomes territorial and even gets into fights.
Often, the fish worries its owner with its peculiar sleeping position while hugging wood or stone. It also moves in its sleep, so don’t misunderstand it as a sign of health concerns.
Lifespan
In captivity, the fish can live for 10 years with the best care and conditions.
Author’s Note: During the day, the fish is as still as a rock and is often found lying on the bottom. However, its true majestic form unfurls right after dusk. It starts swimming around the bottom layer of the aquarium, looking for food.
Royal Pleco Care
To help your royal pleco live up to its entire lifespan, you must ensure that it has a suitable environment. So, here are a few things to remember!
Tank Size
The fish is territorial and needs a lot of space to swim around. So, it needs at least a 125-gallon tank to stay healthy and happy. Make sure it is 24 inches wide from the front to back, as it doesn’t enjoy cramped spaces.
Water Chemistry
The water quality plays a major role in your pleco’s health. A sudden change in parameters can lead to severe health concerns. So, follow this chart… to the T!
- pH Levels: 6.5-7.5
- Water Temperature: 70-86 °F (21-30 °C)
- Water Hardness: 9-19 dGH
- Carbonate Hardness: 0-30 dKH
- Ammonia: 0 ppm
- Nitrite: 0 ppm
- Nitrate: Below 30 ppm
Tank Environment
Next up, your goal is to make your pleco happy and feel at home. So, let’s furnish the tank accordingly!
Substrate
Since the stomach of the pleco is soft and it’s a bottom feeder, you must use a soft sand substrate. You must use smooth gravel, but check that they aren’t too small. Otherwise, the pleco might assume it’s food and eat it.
Plants
They don’t particularly have any fondness for vegetated setups. Since they are primarily herbivores, they may even eat your plants.
For the same reason, avoid using any sort of plastic in the aquarium, or the fish may ingest it and get sick.
Lighting
In the wild, the fish inhabits muddy freshwaters around rocks and large roots. So, it prefers to be in a shaded region to protect itself from predators. To imitate that, use low or dim lights.
Décor
As mentioned above, any kind of plastic decor is a big NO. However, you can add bogwood and driftwood to the décor. The fish also scrapes the soft outer part of the wood, so that’s also a feast for it!
Filtration
The adult fish is big and will excrete a lot, leading to high nitrate and nitrite levels. So, use a reliable and rugged oversized oxygenating filtration system or two small ones.
Water Flow Rate
In the wild, the fish is seen in both fast-flowing and slow-moving waters. So, it doesn’t hurt the fish either way. But a fast-moving water flow will ensure a clean tank, so go for that!
Fish Care Tip: Never let the tank temperature reach 91 °F (33 °C) or beyond for long periods to keep your fish healthy and for longer years.
Food & Diet
The fish is primarily herbivorous, so a considerable part of its diet is plant matter like algae, plant waste, wood, and organisms that break down wood.
But that won’t be enough for it, so here are a few different feeds to keep your fish healthy.
- Algae wafers
- Sinking food pellets
- Blanched vegetables
- Broccoli
- Spinach
- Cucumbers
- Zucchini
- Peas
- Flakes and frozen food
It can also have a carnivorous and insectivorous meal but can’t digest such feed well. So, feed these twice a week:
- Daphnia
- Insect larva
- Bloodworms
- Live and frozen brine shrimp
- Fish
- Crustaceans
- Fish eggs
- Beef heart
- Cichlid pellets
This will give them enough nutrients and energy to explore the aquarium. Make sure to feed the fish after dusk and before it dozes off.
Don’t give your fish bread or Tubifex worms, as they aren’t digestible to this species. You must also not overfeed the fish and regularly get rid of leftovers the next morning.
But to know the right portion of food for your pleco, you need to experiment, as not all plecos have a similar appetite.
So, feed them whatever is advised by your seller for a few days. Then, try feeding it some more. If there is no remaining food in the aquarium bottom in the morning, it is hungry.
On the other hand, if the entire excess food is left over, your fish is properly fed. If the excess food is partly left, reduce the extra food slightly every day to figure out the perfect portion.
Tank Mates
This fish is the happiest in a community tank without any other pleco, catfish, or bottom-dwellers around. So, it would be best to choose top and middle-dwelling fish and non-aggressive fish.
The best choices are:
- Bleeding heart tetras
- Congo tetras
- Dwarf gouramis
- Black skirt tetras
- Bloodfin tetras
- Glowlight tetras
- Hemiodus
- Lemon tetras
- Rummynose tetras
Note: Even if some of the fish in the list have fin-nipping or aggressive tendencies, they won’t bother the pleco, especially because:
- They don’t dwell at the same tank level as the royal.
- Their nipping and aggressiveness only apply to their own species.
- They aren’t territorial.
- The pleco, though peaceful to other species, is too big for these species to pick a fight with.
- They won’t nip the pleco’s fins so long there is enough space in the 125-gallon aquarium.
- Pleco is very calm and peaceful so none of the tank mates feel stressed to show aggression.
Tank Mates to Avoid
Keep in mind that plecos are excessively aggressive toward similar species. They fear losing their comfort, space, and even food, so they fight with other plecos and catfish, including corydoras.
They are also slow and have extremely attractive fins. So, never house them with nippy, fast-moving, and aggressive fish; otherwise, the slow-swimming pleco won’t be able to dodge the attacks and may even get brutally hurt.
You must also avoid housing the following fishes:
- Freshwater angelfish
- African cichlids
- Bumblebee gobies
- Bettas
- Goldfish (Ryukin and Shubunkin)
- Flag cichlids
- Kissing gouramis
- Malawis
- Smaller plecos
- Corydoras
- Siamese fighting fish
- Skunk loaches
- Rosy barbs
- Black ruby barbs
- Tiger barbs
- Black skirt tetras
- Bloodfin tetras
- Mollies
- Silver dollar fish
- Chalceus
- Jaguar cichlids
- Headstanders
Common Diseases
The fish is extremely hardy and hardly gets sick in the wild. But while keeping it in a restricted environment, you must be cautious of the following…
| Disease Name | Causes | Symptoms | Treatment |
|---|---|---|---|
| Ich | Parasitic protozoan infection | White spotting, inactivity, flashing, appetite loss | Raise aquarium temperature, add salt or ich medicines |
| Fin and tail rot | Bacterial infection | Fin and tail fraying or disintegrating, appetite loss, inactivity | Elevate water quality, get rid of physically injurious objects, and treat with antibiotics |
| Columnaris | Bacterial infection | Color loss and white patches, fin fraying, appetite loss, inactivity | Maintain better water quality, reduce stress, and treat with antibiotics |
| Dropsy | Stress, water quality degradation, malnutrition | Inactivity, swollen belly, bulging eyes, color loss, stringy and pale feces, clamped fins, appetite loss | Quarantine, add salt or medicine, balanced and high-quality diet |
| Pop-eyes | Immune response from injury | Swollen and protruding eyes | Frequently change water, quarantine, add salt, offer a balanced diet, treat with antibiotics |
| Hole in the head | Protozoan parasitic infection | Loss of appetite, color loss, hemorrhage on head, red feces | Swift antifungal treatment |
| Septicemia | Bacterial infection | Abnormal behavior, bleeding, protruding eyes, anemia, bloated belly | Quarantine and treat with antibacterial and antifungal medicines like Kanaplex |
Disease Prevention Tip: Keep it in a social and peaceful community of other species; otherwise, it might get stressed and sick.
Breeding & Reproduction
Until now, there has been no report of breeding this species in a controlled or captive environment. The species is only bred by specialists with ample knowledge and care. However, it readily breeds in the wild.
As mentioned repeatedly, the fish is highly territorial and aggressive to its own kind. So, it might result in a disaster if you don’t know the right way.
According to my experience, amateur aquarists hardly have success rates in breeding this. So, you must induce the mating process only if you have long years of expertise with fish-keeping.
Pair Choosing
If possible, get a mated pair from the store. You can also talk with a professional royal pleco breeder for more information.
Otherwise, you may have to house multiple fish together to let them choose their mate. You will need a much larger tank to keep them.
Again, you need expert support to ensure no fish gets hurt in the process.
If you successfully find a mated pair, then move on to the next step. Otherwise, you might risk losing your plecos. So, don’t take this lightly!
Tank Preparation
Take a separate 125-gallon tank with a tight lid and create many hiding spaces. In the wild, the fish breeds in the rainy season. Introduce the mated pair to the tank and mimic a dry season first with slightly warmer and inactive water for a few days.
After a few days, start mimicking the rainy season and maintain the following water conditions:
- Slightly acidic water: pH Level 6.5-7.0
- Temperature: 72-78 °F (22-25 °C)
- Water hardness: slowly increase the softness
Fish Conditioning
Meanwhile, feed both fish a veggie and meaty diet to maintain the best health conditions. You can also provide it with vinewood and other digestible feed.
Mating
If your pet fish responds to this setup well, the male will stimulate the female. The female fish will lay eggs on a rock, wood, or debris in the tank bottom, and the male fish will fertilize the eggs.
You must turn off any high-power filtration or substrate vacuum during this time. The male fish will guard the eggs throughout the incubation period (5-7 days).
Fry Development
Before the eggs hatch, remove the parent pair from the breeding tank to prevent them from consuming fry.
Feed the fry crushed flakes and baby brine shrimp. Once they are a bit older, you can rehouse them in a community tank of small peaceful species.
Breeding Tip: You can also use actual rainwater to increase breeding chances.
Don’t try to reproduce the fish if you’re:
- Not an expert
- Can’t connect with an expert with experience in reproducing
- Don’t have a mated pair
Quick Buying Tips
The fish is not readily available in stores. Since they mainly reproduce in the wild, stores catch one from the wild whenever they get orders. So, find your nearby store, place an order, and patiently wait for the store to ship your fish.
A word from FIA
Royal plecos are great ornamental species as they are easy to care for. They aren’t high-maintenance and can eat almost anything. It doesn’t even need special decorations to feel happy. So, if you have a large tank, this is a must-try!
If that answers all your queries, make sure to share it with your fish-enthusiast friends. And if there’s any other concern, feel free to drop a mail and we’ll get back to you ASAP.