Bristlenose Pleco
Also known as: Ancistrus cirrhosus
The Bristlenose Pleco (Ancistrus cirrhosus) is a small, armored catfish native to the Amazon Basin, distinguished by the fleshy tentacles (bristles) on the snout of mature males. The Bristlenose Pleco originates from Amazon River basin in South America, including Brazil, Peru, and Bolivia, reaches 12-15 cm in captivity, typically lives 10-15 years, and is kept at 22-28°C (72-82°F). Individual fish vary, so treat this as a general guide rather than a guarantee.
Key facts
- Lifespan: 10-15 years.
- Adult size: 12-15 cm (4.7-5.9 inches).
- Temperament: Peaceful and nocturnal; generally non-aggressive toward tankmates.
- Minimum tank: Minimum 75 liters (20 gallons) for a single fish; 115 liters (30 gallons) recommended for a pair or small group.
- Water temperature: 22-28°C (72-82°F).
- pH range: 6.5-7.5.
Species at a glance
- Origin
- Amazon River basin in South America, including Brazil, Peru, and Bolivia
- Adult size
- 12-15 cm (4.7-5.9 inches)
- Life span
- 10-15 years
- Temperament
- Peaceful and nocturnal; generally non-aggressive toward tankmates
- Tank size
- Minimum 75 liters (20 gallons) for a single fish; 115 liters (30 gallons) recommended for a pair or small group
- Water temp
- 22-28°C (72-82°F)
- pH range
- 6.5-7.5
- Diet
- Primarily herbivorous; feeds on algae, biofilm, and vegetable matter; supplement with sinking algae wafers, blanched zucchini, cucumber, and occasional protein sources like bloodworms
- Other names
- Ancistrus cirrhosus
About the Bristlenose Pleco
The Bristlenose Pleco (Ancistrus cirrhosus) is a small, armored catfish native to the Amazon Basin, distinguished by the fleshy tentacles (bristles) on the snout of mature males. It is a hardy, bottom-dwelling species valued in aquariums for its algae-eating habits and peaceful nature. Unlike larger plecos, it remains manageable in size and is well-suited to community tanks. Its nocturnal behavior means it is most active during low-light periods, often hiding in caves or under driftwood during the day.
Lifespan and health
With proper care, Bristlenose Plecos commonly live 10-15 years in captivity, with some individuals exceeding 15 years under optimal conditions. Lifespan is strongly influenced by diet, water quality, and stress levels; fish kept in overcrowded tanks or fed excessive protein often show reduced longevity. Regular monitoring of behavior and appetite is key—healthy individuals are active at night, maintain a rounded belly, and show clear eyes and intact fins. Common health issues include bacterial infections (often from poor water quality or injury), fungal growth on damaged skin, and parasitic infestations like Ichthyophthirius multifiliis (Ich), especially if new fish are quarantined improperly. Obesity and fatty liver disease can occur from overfeeding protein-rich foods, leading to lethargy and buoyancy problems. Preventative measures include maintaining pristine water, providing a varied vegetable-based diet, avoiding overcrowding, and quarantining new arrivals for 2-4 weeks before introduction.
Overview
The Bristlenose Pleco (Ancistrus cirrhosus) is a small, armored catfish native to the Amazon Basin, distinguished by the fleshy tentacles (bristles) on the snout of mature males. It is a hardy, bottom-dwelling species valued in aquariums for its algae-eating habits and peaceful nature. Unlike larger plecos, it remains manageable in size and is well-suited to community tanks. Its nocturnal behavior means it is most active during low-light periods, often hiding in caves or under driftwood during the day.
Care and tank setup
Tank setup should include a soft sand or fine gravel substrate to protect the fish’s delicate barbels, along with ample hiding places such as driftwood, rock caves, and PVC pipes—bristlenose plecos are territorial and require personal space. Provide moderate to low lighting and include live plants like Java fern or Anubias, which they won’t uproot. A minimum tank length of 60 cm (24 inches) is advised to allow for adequate swimming and foraging space. Water conditions must be stable: maintain temperature between 22-28°C (72-82°F), pH 6.5-7.5, and hardness of 5-15 dGH. Perform weekly 25% water changes to keep nitrates below 20 ppm; use a gentle filter flow as they prefer calm zones. Avoid strong currents that stress their sedentary nature. Ensure good oxygenation, especially in warmer tanks, as they are sensitive to low dissolved oxygen. Feed a diet rich in vegetable matter: offer sinking algae wafers 3-4 times weekly, supplemented with blanched vegetables (zucchini, cucumber, spinach) 2-3 times per week. Remove uneaten food after 24 hours to prevent fouling. Provide occasional protein treats like frozen bloodworms or brine shrimp once a week. Avoid overfeeding—bristlenose plecos are prone to obesity if fed too much protein or high-fat foods.
Sources
Related breeds
Breed information on this page is based on the Wikipedia article on the Bristlenose Pleco, supplemented with additional research. Reviewed for accuracy.