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Bristlenose Pleco: A Detailed Care Guide

Bristlenose Pleco: A Detailed Care Guide

If you’re looking for a small pleco variety for your tank, you may have considered the tiny Bristlenose Pleco with its beautiful yellow spots. Is there anything you need to know before adopting one?

Bristlenose Plecos are small fish with unique tentacle-like whiskers growing from their snouts. They have dark bodies with yellow spots and pronounced lips on their sucker mouths. The ideal tank size is 25 gallons/114 liters, and they are easy to breed. 

In this article, I’ll explain all you need to know about owning a Bristlenose Pleco, from the ideal tank conditions, the perfect diet, and what to put in the tank. Let’s dive right in! 

Bristlenose Pleco Overview & Natural Habitat

  • Common name: Bristlenose Pleco, Bristlenose Catfish, or Bushy Nose Pleco
  • Scientific name: Ancistrus cirrhosus
  • Care level: Easy and ideal for beginners
  • Size: 3 to 5 inches/7.6 to 12.7 cm
  • Lifespan: 10 to 12 years
  • Temperament: Calm, quiet, and shy
  • Diet: Omnivorous
  • Group size: Solitary fish
  • Minimum tank size: 25 gallons/114 liters
  • Tank level: Bottom dwellers
  • Water temperature: 60 to 80°F (15.5 to 27°C)
  • Water pH levels: 6.5 to 7.5
  • Water hardness: 6 to 10 KH

Bristlenose Plecos are tiny pleco fish with tentacle-like outgrowths that extend from their snouts and mouths (in the case of males). This is the reason they are sometimes referred to as “Bushy Nose Plecos”. 

They have dark bodies with yellow spots and large fins. 

This pleco fish originates from the freshwater channels of Central and South America and are occasionally found in floodplains.  

Bristlenose Pleco Appearance & Size

Bristlenose Plecos have dark-colored bodies, which are usually black, muddy green, dark brown, or brown-gray. They have yellow spots against the dark background, which also extend to the fins. 

The dark color becomes slightly lighter toward the fish’s belly, and the fins are fanned and fleshy. 

Like other plecos, they have “sucker” mouths, but Bristlenose Plecos have more pronounced lips and also broader heads. They have stocky bodies with bony armor, which affords them protection from larger fish. 

Their tentacle-like outgrowths from the snout give them an interesting appearance that some pet owners find intimidating. Still, because they’re so small, most people find them to be adorable tank additions and find them rewarding to own.  

In terms of size, Bristlenose Plecos are one of the smallest pleco varieties and reach an adult size of only 3 to 5 inches/7.6 to 12.7 cm.

Difference Between Males and Females 

The main difference between male and female plecos is the size and location of the whiskers. 

Male Bristlenose Plecos have longer and thicker whiskers around the snout area, while females have more delicate tentacles that typically only grow around the mouth. 

Males and females are typically the same size and have the same coloration. 

Bristlenose Pleco Personality & Behavior

Bristlenose Plecos are placid and shy and can become fearful and hide away if they don’t feel safe. 

Like most plecos, Bristlenose Plecos are nocturnal, and you’ll only see them swimming around the tank when it gets dark. During the daytime, it can be difficult to spot your Bristlenose Pleco, as it’s probably sleeping in one of its favorite hiding places.

Even so, they don’t often swim around rapidly and prefer to slowly explore the tank substrate and interesting places within the aquarium. 

Bristlenose Pleco Average Lifespan

In the wild, Bristlenose Plecos usually have a lifespan of 10 years, which is impressive for such a small fish species. 

That said, many Bristlenose Pleco owners have reported that their pets have lived to 12 years, likely because they received a well-balanced diet and always enjoyed excellent tank conditions. 

Bristlenose Pleco Care & Tank Set Up

Here’s what to consider when setting up your Bristlenose Pleco’s tank: 

Aquarium Nitrogen Cycle

The nitrogen cycle is one of the most important aspects of fishkeeping as it maintains a safe ecosystem for fish to thrive in the aquarium.

A common mistake for beginners (new tank syndrome) is either not knowing about the nitrogen cycle or not keeping it in mind when maintaining the water.

What Is An Aquarium Nitrogen Cycle?

The nitrogen cycle is the process by which beneficial bacteria convert fish waste and uneaten food in the aquarium into less harmful substances. The cycle is crucial for maintaining a healthy and stable environment for fish and other aquatic animals.

In new aquariums, there may not be enough bacteria to break down fish waste, resulting in an unhealthy buildup of ammonia and nitrite. This is not visible to the naked eye, so it’s important to regularly test the water with a kit to ensure the smoothness of the nitrogen cycle.

What Happens If I Don’t Complete A Nitrogen Cycle?

Failing to complete regular nitrogen cycles can lead to the accumulation of harmful substances like ammonia and nitrite. These substances can cause stress and damage to fish, leading to health problems and if left unchecked it will eventually kill everything in your aquarium.

By maintaining a healthy nitrogen cycle, you can ensure a long and healthy life for your fish. 

Remember to always keep the nitrogen cycle in mind when caring for your aquarium.

Tank Size

Even though Bristlenose Plecos are small fish, they need plenty of space to explore their surroundings, scavenge for food, and relax. 

An adult Bristlenose Pleco needs a tank that’s at least 25 gallons/114 liters in capacity, and you may consider a larger one if you have the space and budget.

How Many Bristlenose Plecos Are Suitable for a 25-Gallon Tank?

Bristlenose Plecos aren’t schooling fish or sociable creatures and prefer their solitude. 

You should have no more than two Bristlenose Plecos for a 25-gallon tank, and you shouldn’t keep two males together as they will fight and become stressed as they battle for territory. 

Water Parameters

  • Water temperature: 60 to 80°F (15.5 to 27°C)
  • Water pH levels: 6.5 to 7.5
  • Water hardness: 6 to 10 KH

Bristlenose Plecos are fantastic plecos if you’re a first-time owner or you want a fish that is easy to care for. 

Despite this, they need certain water parameters to remain healthy. These include:  

Water Temperature 

A Bristlenose Pleco needs its tank water temperature to be between 60 to 80°F (15.5 to 27°C), as this mimics its natural habitat in the Amazon. 

This is a fairly wide temperature range, and it shouldn’t be difficult to achieve this. Still, you should consider investing in a tank thermometer to monitor the temperature. 

Water pH Levels

In the wild, Bristlenose Plecos live in neutral-pH water but will tolerate very slightly acidic or alkaline water. The optimal pH range for Bristlenose Plecos is between 6.5 to 7.5.

It’s advisable to monitor the tank’s pH every few days to ensure it always remains within this range, and you can do this with a pH measurement tool that you can buy online or from a pet store. 

Water Hardness

Water hardness refers to the number of minerals present and the fewer minerals, the softer the water. Bristlenose Plecos can tolerate a water hardness level of between 6 and 10 KH, which is soft to mildly hard. 

Water Current 

As South American fish, Bristlenose Plecos are habituated to fast-flowing rivers with strong currents. Installing a good quality water pump will help you to achieve the same conditions and will keep your Bristlenose Pleco happy. 

What To Put In The Tank

Providing the correct size tank for your Bristlenose Pleco is important, but it also needs other things to be happy and feel safe:


The perfect tank substrate for a Bristlenose Pleco’s tank should consist of a mixture of the following elements: 

  • Sand
  • Fine, round gravel
  • Clay

This gives them a great surface for exploring and searching for loose pieces of food. 


Bristlenose Plecos are small fish and in the wild, their natural instinct is to hide in aquatic vegetation and hollow rocks. 

With this in mind, you should provide a lot of hiding places for your Bristlenose Pleco by decorating the tank with items such as: 

  • PVC pipes
  • Decorative tank castles
  • Hollowed-out wood or rocks

Driftwood is another essential tank element as it allows the Bristlenose Pleco something to nibble on and provides additional fiber. 

Ideal Plants

Bristlenose Plecos have prominent lips on their sucker mouths, which facilitates algae eating. They love eating algae off the inner surface of the tank or plants. 

The perfect plants for a Bristlenose Pleco include: 

These aquatic plants provide the shade that Bristlenose Plecos love and also have broad enough leaves to make your fish feel safe and hidden. 


Bristlenose Plecos don’t typically need any tank lighting because they enjoy low-light conditions and shade within the aquatic vegetation. 

You only need to think about using a tank light if the aquarium is located in a very dark place because a little light is needed to promote algae growth. 


Using a tank water heater for a Bristlenose Pleco’s aquarium also isn’t usually necessary because they’re tolerant to a pretty wide temperature range (60 to 80°F/15.5 to 27°C).

However, you should still monitor the temperature just to be sure that your Bristlenose Pleco is happy and comfortable. 


Bristlenose Plecos are sometimes colloquially known as “tank cleaners” because they eat a lot of the algae present in the tank. Unfortunately, this isn’t enough to keep the tank spotlessly clean, and a canister filter is a good investment. 

If you notice your Bristlenose Pleco at the top of the tank or gasping for air at the water’s surface, it’s probably an indication that there is too much waste matter and nitrates and not enough oxygen. Still, if you have a good filter, this should rarely, if ever, happen. 

Bristlenose Pleco Tank Mates

If you want to introduce other fish to your Bristlenose Pleco’s tank, you need to be careful, as aggressive fish might make them feel threatened and occasionally harm them. 

Excellent tank mates for a Bristlenose Pleco includes: 

Tank Mates To Avoid

Goldfish, discus, and gouramis shouldn’t be added to a tank with a Bristlenose Pleco. In addition, you should also avoid placing two male Bristlenose Plecos together, as they will compete for the same territory, regardless of how large the tank is.  

Bristlenose Pleco Food & Diet

Bristlenose Plecos are omnivores but the vast majority of their diet comes from plant matter. Algae is an essential part of their diet and if you think your tank doesn’t have enough, you can feed them algae wafers. 

In addition, you should feed your Bristlenose Pleco freeze-dried food or sinking pellets once a day, preferably in the evenings when they’re just waking up. If you enjoy feeding your pets homemade food, you can give your Bristlenose Pleco finely chopped blanched vegetables.

You can supplement their diet with bloodworms and small snails every two to three days. 

Breeding Bristlenose Plecos

If you only have a male and female Bristlenose Pleco in the tank, you can allow them to breed there. However, you should strongly consider moving them into a separate tank if there are other fish present, as this puts the eggs at risk of being eaten. 

To encourage your Bristlenose Plecos to breed, make sure the aquarium has plenty of nooks and crannies because they are cave spawners and lay eggs in hollow structures.

Bristlenose Plecos tend to breed in water that is on the cooler side of their preferred temperature range, so you may want to move the tank to a cooler location or dial down the tank water heater a little. 

Once the female has laid her eggs and they’ve been fertilized, the male will take over and protect them until they hatch (which is typically 10 days later).  

Young Bristlenose Plecos are tiny and vulnerable and can benefit from being in a “nursery” tank until they’re large enough to live in the main tank. 

Bristlenose Pleco Common Health Issues

If you take care of your Bristlenose Pleco well, they shouldn’t develop any serious health conditions. 

However, the most common health issue in Bristlenose Plecos is dropsy


Dropsy refers to abdominal or tissue swelling (usually with fluid, such as lymph or water), and it usually occurs when the tank water has been neglected, and bacteria and other pathogens have been allowed to accumulate. 


The symptoms of dropsy in Bristlenose Plecos are easy to spot and usually present as: 

  • Swollen abdomen
  • Bulging eyes
  • Lack of coloration
  • Weight loss
  • Lethargy
  • Distorted scale pattern

Before you treat your fish for dropsy, it’s important to take a few precautionary steps first.

  • Check water quality: Check the pH, nitrate, and temperature levels, and ensure your filter is working correctly. Maintaining a healthy tank can help prevent any deficiency that can lead to dropsy.
  • Isolate your fish: Even though dropsy isn’t always contagious, I recommend placing your fish in Isolation. Putting your Bristlenose Pleco in a quarantine tank allows you to treat it in a controlled environment and take precautions not to infect other fish.


To treat dropsy, it’s important to pinpoint what is causing it. It can be caused by bacteria, fungi, or parasites, which usually happens when you don’t filter the water effectively or allow the nitrate levels to become elevated. 

  • Antibacterial Medication: A quick and easy way to treat dropsy is with antibacterial medication. Always follow directions for duration and dosage.
  • Epsom Salt Treatment: Epsom salts will help relieve swelling. Once you have your fish isolated, you can add Epsom salt to its tank. I add 1/8 flat teaspoon per 5 gallons to every gallon of water. Routinely change the water, making sure you maintain 1/8 flat teaspoon of salt for every 5 gallons of water.  I change 25% of the water every 2 days. Don’t use any other type of salt to treat dropsy or you could worsen the condition.
  • Maintain a Healthy Diet: Make sure you provide your Bristlenose Pleco with a fresh high-quality diet.

I always recommend speaking with your local pet store or aquatic veterinarian.


Dropsy is an uncomfortable condition for Bristlenose Plecos, and you can prevent it from happening by providing your fish with a healthy diet, making sure you don’t overfeed them, keeping the tank water as clean as possible, maintaining their water parameters, ensuring the filter always functions correctly, and monitor the nitrate levels closely. 

Are Bristlenose Pleco Right For You?

Bristlenose Pleco is right for you if you want a small fish with beautiful spots throughout its body. You also need to be happy to have a 25-gallon/114-liter tank and should be prepared to feed your fish once a day.

Bristlenose Pleco FAQ

How Big Do Bristlenose Plecos Get?

Bristlenose Plecos don’t get big and grow to an adult size of only 3 to 5 inches/7.6 to 12.7 cm. They are considered one of the smaller pleco varieties. They make excellent pet fish if you want a small pleco species and prefer a small aquarium. 

Do Bristlenose Plecos Clean Your Tank?

Bristlenose Plecos clean your tank but only to a certain degree. They like eating algae and decaying plant matter in the tank, but you shouldn’t rely on them solely to keep your tank clean.

With the waste matter they produce, it’s a good idea to use a tank filter and monitor the nitrate levels. 

Are Bristlenose Plecos Hard To Keep?

Bristlenose Plecos aren’t hard to keep. They don’t need much to be happy but do require certain temperature, pH, and water hardness levels to remain healthy. They need to be fed once a day.

Bristlenose Plecos are great for beginners, and keeping them is a fantastic way to introduce yourself to the wonderful world of Plecos. 

Will Bristlenose Plecos Eat Small Fish? 

Bristlenose Plecos typically don’t eat small fish. On the rare occasion that a Bristlenose Pleco can’t find any food, including algae, it may resort to eating a dead fish to prevent starvation. Since algae is usually widely available in tanks and in the wild, this rarely happens. 

Wrapping Up

Bristlenose Plecos are tiny pleco fish with dark bodies and yellow spots that extend throughout the body. They are independent fish that need only the correct food and tank parameters to be happy, making them fantastic plecos for beginners. 

They live at the bottom of the tank and are omnivorous (although most of their diet consists of algae and other plant matter).

I’m Elle, the founder of FishHQ. I created this website to share knowledge, tips, and inspiration for beginner hobbyists to help them create a healthy, happy, and vibrant environment for their fish to thrive. Read more...