Royal Pleco 101: Care, Size, Growth Rate, Food & More!

Royal Plecos are an incredibly unique freshwater fish that will draw attention in any tank.

These large, interesting-looking fish are quite popular among aquarists for obvious reasons. Not only do they bring a neat aesthetic to the tank, but they’re low-maintenance as well!

However, it’s important to have a good understanding of their baseline care requirements before you get one yourself. These creatures can be sensitive to suboptimal tank conditions and need to be kept by an owner who understands their needs.

But don’t worry, this guide will get you up to speed on everything you need to know about Royal Pleco care. By the time you’re done reading it, you’ll be ready to purchase one for yourself!

Species Summary

While Plecos are nothing new to the aquarium trade, the Royal Pleco (Panaque nigrolineatus) is sought-after species with a lot to offer. Not only are they beautiful, but they have some distinct biological quirks that make them an interesting addition to your tank.

These fish originate from several countries in South America. They can be found living in Amazon and Orinoco River basins.

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There are several subspecies included in the larger Royal Pleco family. These all take on similar appearances and require the same care. Though, some minor physical differences among regional variances do exist.

Regardless of the type of Royal Pleco you get, caring for these creatures can be a rewarding experience. Thanks to their docile nature and unique behavior, they make great additions to larger community tank environments.

Average Royal Pleco Size

The average Royal Pleco size when fully-grown is around 16-17 inches in length! Like many other types of Plecos, the max size of this species can get quite large (they have a fairly slow growth rate as well).

That said, some varieties can get even bigger. For example, the Black Royal Pleco is known to reach lengths of 24 inches in the right conditions!


With the right care and living conditions, the average lifespan of a Royal Pleco is 10 years. This is by no means the ceiling, as many have lived for much longer. In fact, these fish commonly outlive their tank mates, requiring long-term dedication to their well-being.

Of course, there are no guarantees when it comes to life expectancy. Like any other fish species, Royal Plecos are directly affected by the level of care they receive.

Author Note: Despite their long lifespan, these fish tend to be rather sensitive to environmental changes. The key to helping Royal Plecos live as long as possible is to follow established and consistent care guidelines by remaining vigilant about tank maintenance.


Royal Plecos have a bold and somewhat intimidating look. Not only are they large, but they have some unique physical features, too.

This species has the recognizable Pleco profile. They have a large head, downturned sucker mouth, and large fins. However, Royal Plecos are slightly different in terms of mass.

Royal Plecos are a bit girthier than other species. Most of that mass is situated on the head, making the fish look taller and stronger.

A Royal Pleco swimming in a freshwater aquarium

The mouth is very large and features spoon-shaped teeth. To facilitate their appetite for wood, these teeth are sharp. They’re perfect for scraping off algae and peeling away wood bit by bit.

On top of the head, the Royal Pleco has bright red eyes! It offers a stunning contrast against the muted tones of the body.

There are a few different color variations among the numerous subspecies. However, the most common color morph you’ll see in the trade is gray and black. The base color is usually light gray. It can sometimes also take on a brownish hue.

Accompanying that base color are bold stripes of black or dark brown. The stripes run laterally along the entire length of the fish. The stripes are imperfect, creating a distinct pattern from fish to fish. The tip of the expansive dorsal fin is covered in a creamy gold color.

You might also encounter black Royal Plecos or those that have spots rather than stripes. For the most part, these varieties are rare in the fish trade.

Like other Plecos and catfish species, the Royal Pleco does not have scales. Instead, it’s covered in tough armor-like skin plates. Although these plates cover the entire body, the belly is much softer.

Royal Pleco Care

Royal Pleco care isn’t very complicated. In fact, many consider them to be one of the easier Pleco species to keep.

However, that doesn’t mean that Royal Plecos don’t need special attention.

These are large fish with unique feeding habits! It’s important to plan their habitat to fit their lifestyle. Below are the essential care guidelines to get you started.

Tank Size

A sizable tank is essential for Royal Plecos. At the very least, you’re going to need an aquarium that can hold 120 gallons!

It’s not just volume that you need to pay attention to. The width of the tank should be at least 24 inches from front to back.

This matters because Royal Plecos are not strong swimmers. While they enjoy exploring the tank, they can have a hard time turning around in cramped spaces.

Author Note: As always, a larger tank is always better if possible. In our experience, the Royal Plecos that live the longest always seem to be in the largest tanks!

Water Parameters

Royal Plecos are tropical fish that need warm waters, and the best course of action is to replicate their natural environment as closely as possible. The rivers they occupy in the wild are warm, dark, and full of food sources.

Royal Plecos prefer water that’s relatively neutral and slightly hard. As a result, you may have to take extra measures to get things right. If your tap water is soft and acidic, consider using something like aragonite in your filter.

Here are some crucial parameters to stick to:

  • Water Temperature: Between 72°F and 78°F
  • pH Levels: 6.6 to 7.5
  • Water Hardness: 5 to 10 dKH

Because these fish lack scales, they are a bit more sensitive to extreme fluctuations in the water. It’s important to test conditions regularly and change about 25 percent of the water on a weekly basis.

What To Put In Their Tank

When you’re decorating the aquarium, pay close attention to the bottom of the tank. Royal Plecos are bottom-dwellers and rarely go to the surface.

The bottom should be covered in a soft substrate, such as sand. Gravel is suitable as well.

However, you need to make sure that the individual pieces are not small enough to swallow, which can be a challenge due to the Pleco’s size.

As for decorations, the most important thing to incorporate is driftwood. Royal Plecos are one of the few species that have symbiotic gut bacteria to safely digest wood. They take full advantage of this!

Incorporate large pieces of driftwood throughout. The wood will act as a food source while also facilitating the growth of algae.

Whether or not you choose to incorporate plants is up to you. Royal Plecos do fine with or without.

However, if you do want to use plants, you need to make sure that they’re real.

These fish are known to chew holes through plant leaves. They are unable to digest silk or plastic plant parts, which can result in an impaction.

Without plants, you can keep lighting levels relatively low. Royal Plecos are naturally nocturnal. Not only that, but the rivers they come from in the wild are murky. Low light levels help to replicate that experience without having to affect the color of the water.

Strong filtration is paramount for a fish of this size! They produce a lot of waste, so you need to ensure that your filter is strong enough to cycle the tank. We recommend something robust like the Fluval FX4.

Not only that, but you need to create a strong flow. The presence of driftwood creates natural dead zones where waste can settle and affect water quality. Incorporate extra powerheads to keep the flow strong throughout.

Common Possible Diseases

Royal Plecos are at risk of experiencing many of the standard freshwater diseases. However, these fish require different treatments.

For example, these Plecos can suffer from Ich which is a highly contagious protozoan disease. Typically, this can easily be treated with copper-based medicines, but that’s not the case with Royal Plecos.

The lack of scales makes them very sensitive to copper. So, you’ll have to quarantine the fish and slowly raise the water temperature over several days.

Royal Plecos can also suffer from issues like fin rot and other bacterial infections. The same goes for fungal infections. Luckily, those ailments can easily be treated with Pleco-approved medicines.

Author Note: The best way to avoid diseases is to stay on top of tank conditions. Most ailments are caused by poor living conditions and stress factors. Royal Pleco care is always easier when you can prevent problems instead of treating them.

Food & Diet

As we mentioned earlier, Royal Plecos have a healthy appetite for wood! You’ll see them chowing down on driftwood pretty frequently.

But that’s not the only thing they eat.

These fish also eating aquarium algae and plant detritus. They are natural herbivores, so there’s plenty of food sources for them in the tank. Of course, you can’t rely on natural scavenging alone to keep the fish healthy.

Commercial algae wafers and sinking food pellets should be the diet staple. You can supplement those dry foods periodically with blanched vegetables. Royal Plecos enjoy zucchini, peas, and cucumbers.

Behavior & Temperament

Royal Plecos are generally very docile. They stick to the bottom of the tank and don’t pay any attention to fish occupying other parts of the water column.

The only exception is other Royal Plecos and catfish species. These fish are known to be very territorial with their own species! As a result, multiple Royal Plecos should never be kept in the same tank. Otherwise, you may encounter fighting!

Throughout the day, Royal Plecos will usually hide under driftwood or among plants you might have in the tank. They’re nocturnal, so they tend to be shy during the day.

Author Note: Once the sun sets, they will become more active. The fish will explore the tank looking for sources of food. They’re not the strongest swimmers, but they can get by as long as the tank isn’t too crowded.

Tank Mates

As long as there are not other Plecos or catfish species present, Royal Plecos do just fine in a community tank.

However, there are a few things to keep in mind when choosing tank mates.

The first is what part of the tank they occupy. Royal Plecos stick to the bottom, so you can easily find fish that live in the middle and upper parts of the aquarium to ensure everyone has enough space.

Another thing to think about is the Royal Pleco’s swimming abilities. They are not powerful swimmers. Thus, they cannot get out of harm’s way quickly if things get hairy.

Avoid fast-swimming fish that like to peck at fins. While they won’t cause any serious harm to the Royal Pleco, they will often swim down to the bottom and bite into the dorsal fin. This can make life stressful for the Royal Pleco and open them up to disease.

Generally, non-aggressive fish species that originate from the same area are good options. Here are a few ideas:


Breeding Royal Plecos is a difficult task. It’s pretty rare for owners to successfully breed these fish. It’s done by professional breeders, but there are far too many factors out of your control in a standard tank.

Furthermore, this species’ penchant for aggression against their own kind can make things very complicated.

If you’re lucky enough to come across a bonded pair, you can try your luck. The best way to go about breeding is to simulate the breeding season in the wild. This usually occurs during the rainy season.

With heavy rains come changes in water conditions. Slowly raise the acidity levels. Soften the water a bit and decrease the temperatures, too.

To trigger breeding, you can try feeding your fish plenty of high-quality foods. Vinewood is a favorite among breeders because it’s soft and easy to digest.

If successful, the female will lay her eggs at the bottom of the tank. Typically, the eggs will be laid in a pile of debris. So, you might want to hold off on vacuuming the substrate if you’re trying to breed your Plecos.            

Now You’re Ready

As you can see, Royal Pleco care isn’t overly complex. All it requires is some foundational knowledge about the needs of these fish, and the dedication to maintain their tank.

These freshwater fish are one of the most interesting species out there. We trust that if you get one you won’t regret it in the slightest!

If you have any lingering questions about these fish that our care guide didn’t cover, feel free to get in touch with us. You can either ask us through the contact page on our website or on Facebook!

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