Bristlenose Pleco

Looks how to spot one

Armoured suckermouth catfish

A flattened, bony-plated catfish with a downward-facing sucker mouth for clinging and grazing. Adult males grow a crown of soft, branching tentacles on the snout and head, which gives the fish its name; females have only a few small ones along the edge of the snout, or none. Males also carry small hooked spines on the cheeks that they can flip outward.14

Personality what they are like

Calm and easygoing with other fish, spending much of its time grazing on surfaces or resting in caves. Males can be territorial toward other bristlenoses or similar-shaped catfish, particularly around a favourite cave.15

Daily activity how busy a day looks

Mostly active at dusk and after dark, moving slowly over glass, rocks and wood. Appreciates some water flow, as many species come from flowing streams.16

Grooming and care the hands-on bits

Keep water at about 23 to 27 C with pH around 6.0 to 8.0 and soft to moderately hard water. Good filtration with some current suits it, and caves or hollow pieces of wood give it places to hide and breed.13

Home where they are happiest

Wikipedia suggests a tank of at least about 95 litres (25 US gallons), and FishBase gives a minimum tank length of 80 cm for the larger A. dolichopterus. Provide a sandy or fine gravel bottom, driftwood, rocks and caves.13

Food basics what goes in the bowl

A grazer of algae, biofilm and detritus. Supplement with sinking algae wafers and blanched vegetables such as courgette or cucumber, plus occasional small frozen foods. Despite a popular belief, there is no scientific evidence that bristlenoses actually digest wood.15

Company who they like around

Gets along with most peaceful community fish. Can be kept singly or in groups in a larger tank, ideally with one cave per male to prevent squabbles.15

The story where it all began

The first species of the genus was described in the 19th century, including Ancistrus cirrhosus by Achille Valenciennes in 1836 and Ancistrus dolichopterus by Rudolf Kner in 1854. The genus has since grown to more than 100 recognised species spread across tropical South America. Because it stays small, eats algae and breeds readily in captivity, the bristlenose became one of the most popular suckermouth catfish for home aquariums. The fish in the hobby today are mostly captive-bred, and their exact species identity is often uncertain, which is why they are usually just sold as 'bristlenose' or Ancistrus sp. Breeders have also established albino forms.4615

Recognised by the official bits

IUCN Red List

Ancistrus cirrhosus and Ancistrus dolichopterus both assessed as Least Concern3

Taxonomy

Genus Ancistrus contains over 100 valid species, the largest genus in the tribe Ancistrini1