Bristlenose Pleco Care Guide: Tank, Feeding & Breeding

Written By Lewis German  |  Tropical Fish  |  0 Comments

What are Bristlenose Plecos?

Bristlenose Plecos, Brushnose Catfish or (Ancistrus) are a species of small Plecostomus. They are a highly adapted, tropical, algae eating, armoured Catfish.

The natural bristlenose is characterised as a flat, dark brown fish, with white speckles all over its body, a round suction cup shaped mouth, spiky pectoral fins and a distinctive ornament on the male’s nose (bristles).

Where are Bristlenose from?

Ancistrus are naturally found in the Amazon Basin, in heavily forested areas, where they live in rapids, fast flowing streams and tributaries. They live in caves, rockwork and on decomposing wood where the males establish breeding territories.

Bristlenose in the aquarium hobby however, are slightly different. As they have been domesticated, they are typically smaller than wild Bristlenose and have been bred into longfin and various colour varieties.

The fish you find in your local fish store, will have likely been bred in a farm or in someone’s aquarium.

Water parameters for Bristlenose

Bristlenose Plecos are found within or downstream from forested areas, with lots of rotting plant debris washed down the river. Like most water bodies from forested areas, the rotting leaves and wood create tannins which stain the water brown and lower the pH.

Bristlenose have been bred in captivity for a while now and have become very tolerable of differing water parameters, which is what makes them ideal for all different types of communities.

However, if you want your Plecos to be the most comfortable, it is best to keep them closer to the natural parameters of their wild habitat:

pH6.0 – 7.5
HardnessLow to moderate KH and GH
Temperature23C – 26C (74F – 78F)
Ammonia (NH3)0 ppm
Nitrite (NO2)0 ppm
Nitrate<5 ppm

Feeding and diet of Bristlenose Plecos

Bristlenose, like many other Plecos, have a specialised diet which they have an adapted mouth shape for. They are omnivores, but swing towards the side of herbivory with the majority of their diet being taken up by algae.

Pleco’s diets change throughout their lives and as they are young, they will consume more plant material and algae; but, as they age, they will want a more protein rich diet and will show less and less interest in algae.

Throughout their whole lives however, they still need variety and a mix of plant and veggie matter as well as protein-rich, meaty foods.

In the aquarium, give them lots of variety: 

  • Sinking catfish or high protein cichlid pellets
  • Canned green beans
  • Thawed out frozen peas
  • Boiled cucumber
  • Bloodworms
  • Tubifex
  • Brine shrimp

Plecos also need a portion of their diet taken up by wood. Wood is very important for catfish as it aids in their digestion and absorption of nutrients. It also tends to grow lots of “Biofilm” which is colonies of bacteria growing along the surface of the wood.

Biofilm also takes up a large portion of the Plecostomus diet, as they spend all day and all night grazing on it.

Best tank mates for Bristlenose Plecos

Bristlenose are heavily armoured catfish – they are completely covered in spiky thorns, boney plating and have a bundle of defensive spikes under their gills. Despite this set of weapons Bristlenose possess, they are by nature very peaceful and get along with most other peaceful fish.

They can sometimes become defensive over food, but as long as the other fish stay out of the way, they will be fine.

They can also be housed with semi-aggressive and more territorial fish due to their defensive capabilities and they usually are never picked on, lest one of your fish wants to get a face full of spikes. They are also very hardy and resilient to a wide range of water parameters.


Platies are great with Bristlenose as they live in the upper and middle levels of the tank. They are placid and are not extremely aggressive eaters.

They can also get away quickly if the Pleco becomes defensive over food and they lack any extremities or long fins that could be easily snagged on and shredded by the pleco’s gill spikes.

Platies also require a similar high vegetable content diet and will enjoy eating the same foods as your Pleco. You can even breed Platies in the same tank with the Bristlenose, as despite its large size, they will not eat the babies due to their downturned mouth shape.


Bristlenose go well with Angels – they are too large and too heavily armoured to be eaten or picked on and make great cleanup, eating any food that gets past the Angels.

Angelfish are also slow moving and will not oppose high competition when it comes to eating when housed together.

Bristlenose housed with slow moving and slow eating Angelfish will rarely have a hard time finding food. Angels also like the same type of acidic water that Bristlenose really thrive in, making them ideal tank mates.


Most types of Tetras do very well when housed with Plecos. They live in the upper level of the tank, out of the way and are generally very peaceful fish.

Any food that lands on the floor, Tetras will typically leave behind as they prefer to eat from the surface or upper level. This wasteful nature works to the Plecos benefit, as it means there is plenty of food left over for them.

They will however, still need additional feeding with algae wafers and bloodworms, which are best given in the evening when the Tetras are less active and provide less competition.

Most Tetras also like soft water which again, Bristlenose Plecos really thrive in.

Here are some Tetra species which work particularly well with Bristlenose:

  • Neon Tetra
  • Black Phantom Tetra
  • Emperor Tetra
  • Congo Tetra
  • African Red Eye Tetra
  • Lemon Tetra
  • Black Neon Tetra
  • Diamond Tetra


Most smaller Gourami species will also work excellent well with Plecos. They occupy the upper level of the tank, aren’t aggressive eaters, don’t have long fins which can get snagged and enjoy soft water.

Just be sure you are providing enough oxygen with an airstone, as Plecos live in an environment with strong water movement with high oxygen levels, which is opposite to the habitat of the Gourami which cannot swim against a strong current very well.

An air powered sponge filter or air stone will work well for both species as it does not create a strong current which will blow the Gourami around, but still provides enough oxygen for both species to thrive.

How to breed Bristlenose Plecos

Bristlenose are fairly easy to breed so long as you have the right setup, as the male will look after the eggs and young until they are large enough to leave the nest and find their own food.

Before breeding your Bristlenose, you need to condition them and put plenty of weight on them; especially the male, who needs the extra reserves while he spends all his time sitting on the eggs and fry for the next 2 weeks. Feed your Bristlenose Plecos heavily with green beans, cucumber, blood worms and pellets to put weight on them ready for breeding.

Then set up a breeding tank. Have the lights dim, the pH at around 6.0 – 7.0, keep the water soft and increase the temperature to around 27C / 80F.

Provide plenty of territory for the male in this tank, in the form of rockwork, caves and terracotta pots. Pet stores often even sell special made Pleco breeding tubes which can be laid out in the tank to provide nesting areas.

Once the male is comfortable, he will find a cave he wants to spawn in and will spend most of his time inside it, meticulously cleaning it, and then lining it with mulm for his young to feed on when they eventually hatch.

To induce spawning, increasing aeration and performing a large, cool water change can help a lot and often triggers the female to enter the male’s cave and drop her eggs.

The male will lure the female to his cave, vibrating against her with his fins and bristles until she enters and lays her eggs. Once they are laid, he will kick her out and fertilise them, all the work is now done by him, and she leaves the area.

For this to work in the first place however, you need a male and female.

How to sex Bristlenose Plecos

Bristlenose are very easy to sex once mature, as they are very sexually dimorphic. 

  • The males are very apparent as they typically are the only ones to possess the classic “Bristles” which give them their name. They are characterised as antler-like fleshy growths on the front of the head and are especially exaggerated in males. 
  • Females usually do not have them and just have a rounded off, smooth nose.

In all animal species however, there is variation amongst individuals and you will sometimes see very “masculine looking females” or very “feminine looking males”, an “ambiguous” fish, so to say.

Sometimes, female Bristlenose will possess some bristles on their face, although they are usually not anywhere near as long as the males. Sometimes, males will have very clear faces with shorter and fewer bristles and will appear like females.

This is usually the case for immature specimens, and once they age, their true body proportions will show.

However, if they don’t, there are a few other subtle differences in them:

  • Males are typically larger than females
  • Males have a more broad, rounded snout
  • Males will have slimmer, longer and flatter bodies
  • Females are more plump and round when viewed from above
  • Females have a more narrow snout with a smaller mouth
  • Females are usually smaller than the males, and rarely exceed 5”

Rationing Bristlenose Plecos

Bristlenose are solitary catfish. They spend most of their time occupying their own territory and will attack intruders, which is why they fight in captivity when housed in small aquariums. Male Bristlenose are highly territorial and as a result, they should not be housed with other mature males.

Bristlenose are best housed in male and female pairs in a 1:1 ratio – this allows the male to properly court one female without the disturbance of others, and allows him to properly guard his eggs with minimal stress.

Bristlenose spawning and fry

Male Bristlenose Plecos make pretty good fathers, and once the female has laid her eggs within his cave, he will see her off as she will not look after the resulting offspring.

For the next week or so, he will spend 90% of his time in his cave, fanning the eggs with his fins to keep them oxygenated and cleaning them for fungus constantly. He will rarely come out of his nest even to feed, which is why it is so important to heavily feed the male before breeding them, so that he has plenty of fat reserves to keep him going.

It is also very important not to cause stress for the male during this time, as if overly worked up, he can dislodge his eggs from the cave and without his constant care, they will fungus and die.

After the eggs have hatched, they will emerge as wigglers, with their yolk sack still attached. They will be like this for the next 3 days, until they turn into free swimming fry and leave the nest. Once they do leave, they will search the tank for algae and biofilm to feed on.

Baby Bristlenose do really well in very old, dirty tanks with lots of debris and mulm, as it all makes great food for developing fry. Additionally, feed them infusoria, powdered spirulina and eventually, walter worms, tubifex and crushed fish flakes.

Bristlenose usually don’t prey on their young, so they are safe to be left in the tank with the parents, until of course they mature and begin establishing their own territories.

What tank size do Bristlenose need?

Bristlenose are one of the smaller Pleco species out there, reaching around 5” in length on average, although some specimens can be larger. Bristlenose are also territorial by nature to others of their own kind and need plenty of space to graze on and hide amongst.

  • For a single Bristlenose, we recommend no smaller than a 15 gallon tank.
  • For one Bristlenose in a community setting, with other species of fish, we suggest anything above 20 gallons.
  • For a pair of Bristlenose to live in the same tank, we suggest upwards of 30 gallons.

What plants are best for Bristlenose?

Plecos tend to like large, strong, board leaf plants which they can perch on and graze along. They also like to occasionally eat said plants, if they feel that they aren’t getting enough nutrition in their diet.

If you find that your Pleco is eating the plants, then it is an indicator that you aren’t feeding it enough. Plecos also like to burrow in the substrate which can dislodge some shallow rooted plants.

This list contains some plants which are pretty resilient to Pleco abuse:

  • Anubias barteri
  • Java Fern
  • Vallisneria
  • Brazilian Pennywort
  • Pothos (grows out of water)
  • Coontail
  • Elodea densa

Tips and tricks for Bristlenose care

One major tip for Pleco keeping is to make sure that they are well fed!

Even though you might feed your community tank 2 times a day, your pleco may still not be eating as they can be outcompeted easily by other fish during the day.

The best time to feed your Plecos is at night, or in the evening when it starts to become dark as this is when they are most active and when most other fish are going to sleep. Feeding at night time gives your Plecos a better chance at getting food, keeping them healthy and well nourished.