Bristlenose Pleco Fish Species Profile

Characteristics, Origin, and Helpful Information for Hobbyists

Bristlenose Catfish

JanRehschuh / Wikimedia Commons / CC BY-SA 3.0

There are many species of Ancistrus, and several have become prominent within the aquarium hobby. This is attributed to the fact that they stay relatively smaller than their cousin catfish, the pleco stomas, usually reaching only five inches in most species. Having a diet of vegetation, consisting of mostly algae, also makes them an ideal tank addition: they are terrific tank cleaners who will "vacuum" the substrate of your tank on a daily basis. A peaceful and sociable fish, it fits into a community tank nicely. The Bristlenose Pleco is not only an easy fish to care for, it's also unique in appearance and fun to watch.

Species Overview

Common Names: Bristlenose pleco, bristlenose catfish, bushynose catfish, bushy nose

Scientific Name: Ancistrus Cirrhosus

Adult Size: 5 inches

Life Expectancy: 5 years


Family Loricariidae
Origin Amazon, rapid-flowing tributaries
Social Peaceful, suitable for large community tank
Tank Level Bottom dweller
Minimum Tank Size 40 gallon
Diet Herbivore
Breeding Egglayer
Care Easy to Intermediate
pH 5.8 to 7.8
Hardness 2 to 30 dGH
Temperature 73 to 81 F (23 to 27 C)

Origin and Distribution

The Bristlenose Pleco or Ancistrus Cirrhosus originates in South America, mainly in the fast-flowing waters of the Amazon River Basin. They can also be found in some other parts of South and Central America including Panama.

Colors and Markings

The Bristlenose Pleco is one of the smallest catfish, growing to only 3 to 5 inches. They are brown, green, or gray with white or yellow spots; some have uneven coloring, with lighter and darker splotches on various parts of their bodies. Most have lighter abdomens and darker backs (with the exception of the albino Bristlenose, which is mostly white). This species has an unusual appearance, featuring bony plates, a flat, fat body, and a wide head with an "underbite" to the set of the lower mandible.


Any peaceful fish are fine tank mates for Bristlenose Plecos, and they can be kept together with other algae eaters, like snails or grazing fish. They are great for community tanks with species like Neon Tetras, Platys, Guppys, and more. Some aquarists even pair them with known aggressors, such as bettas or African cichlids and even with competitive fish like goldfish. However, when plecos reach maturity, they simply cannot get along with fellow plecos; they can be highly territorial around each other. Therefore, it can be dangerous to house them together at any age.

Bristlenose Pleco Habitat and Care

Naturally, Bristlenose Plecos prefer water that is well aerated with some sort of current. Because they are bottom dwellers, make sure to provide plenty of driftwood, roots, plants, and caves for them to hide in during the day. They are nocturnal and prefer to do their eating mostly at night. Driftwood can provide a good substrate on which algae will consistently grow, giving the Bristlenose Pleco a sufficient amount of food. Although they are herbivores, they will not harm live plants.

Bristlenose Plecos do well in a tank of 20 gallons or larger and can handle a wide range of water conditions from soft and acidic to harder and alkaline. Some hobbyists have found success with Bristlenose Plecos in Cichlid tanks. This may hold true, but it would be best not to keep them with larger Central and South American Cichlids. If you're looking to breed them, do not add into a tank with substrate spawning Cichlids because the Cichlids are likely to devour the eggs.

Bristlenose Pleco Diet and Feeding

Bristlenose Plecos are herbivores, eating mainly algae, so feeding algae or spirulina wafers are best for feeding once or twice daily. Granules, flakes, or bloodworms are also good, while the occasional zucchini slices and blanched romaine lettuce or spinach are good treats. Just make sure to never overfeed. Well-fed plecos have good coloration so it's easy to tell when their nutritional needs are being met. Like all catfish, the Bristlenose Pleco will also spend some of its time foraging through the substrate for algae and other detritus; this, of course, is a great plus as it results in a much cleaner tank.

Gender Differences

This species is relatively easy to breed, and it's quite easy, as well, to determine gender. Both males and females have fleshy tentacles, thus earning the name Bristlenose, but males are usually larger, have whiskers, and have larger bristles. Males' bristles are on their heads, while females are on the snout. Males also have spikes on their fins.  

Breeding the Bristlenose Pleco

Breeding conditions are fairly simple; in fact, the normal tank habitat is nearly ideal. To encourage mating, however, you will probably want to add caves or driftwood to your Bristlenose Plecos' habitat. Once males mature, they will claim a territory that is most suitable for spawning.

The next step is for the female to arrive and lay her eggs during mating season. It's best to do a 75 percent water change to promote mating; their natural mating season is during the Amazon's rainy season, and the change of water can spur mating behaviors (November best aligns with the natural timing of the mating season). The male will defend his territory from other males until a mate finally shows up. Often, fights between males result in their bristles getting tangled together.

Once ready to breed, the female lays her eggs in the male's territory. Eggs are stuck onto hard surfaces such as driftwood, ceilings of caves, PVC piping, or a suitable tank decoration. The male will guard the spawning area for the 5 to 10 days it takes for the eggs to hatch. After hatching, the fry will absorb their egg yolk for a few days, and once finished with that, they will move on immediately to algae.

More Pet Fish Species and Further Research

Small catfish are a terrific addition to a freshwater tank, not only because they're peaceful and easy to care for but also because of their foraging habits which help to keep the tank clean. The Bristlenose Pleco is a great choice for a beginner, but if you’re interested in similar species, check out:

Check out additional fish species profiles for more information on other freshwater fish.