Hypostomus plecostomus
A tropical armored catfish from South America, kept in aquariums for algae control.
This species is a freshwater fish native to northeastern South America. It is widely traded globally as an aquarium cleaner, though it often becomes invasive when released into local waters.
- Native to northeastern South America including Brazil and Trinidad.
- Grows up to 50 cm in the wild but averages 38 cm in aquariums.
- Can breathe atmospheric air by storing it in the stomach.
- Considered invasive in parts of Asia and southern United States.
- Sold primarily for algae control in the aquarium trade.
What it is
The Hypostomus plecostomus is a tropical freshwater fish belonging to the Loricariidae family. It is commonly called the suckermouth catfish or spotted pleco. The body features longitudinal rows of armor-like scutes on the head and back, while the belly has soft naked skin. Adults reach up to 50 cm in length but typically grow smaller in home tanks. They have a dark coloration and a distinctive sucker-like mouth used for adhering to surfaces.
Where it lives
This species originates in tropical northeastern South America. Its natural habitat includes rivers in northeastern Brazil, the Guianas, and Trinidad and Tobago. It prefers water temperatures between 22 and 30 °C with a pH level of 6.5 to 7.5. While native to this region, the name has been misapplied to similar species introduced elsewhere, such as in Central America and parts of the United States.
How it lives
These catfish are omnivorous bottom-feeders that rasp food using their specialized mouths. Their diet consists of algae, aquatic plants, small crustaceans, and various snails. They are nocturnal and semi-aggressive, which helps them avoid harassment from other tank mates. Uniquely, they can breathe atmospheric air by absorbing oxygen in their stomachs, a trait useful in low-oxygen environments.
Fish and people
Aquarists frequently purchase this fish to clean algae from tanks. Despite its reputation as a cleaner, it produces significant waste. In its native range, it is occasionally eaten, though it holds little value as a food fish. Confusion in the trade means many fish sold as this species actually belong to different genera, particularly Pterygoplichthys.
Status and threats
The species has become invasive in several countries outside its native range. Governments in Bangladesh, India, Malaysia, Indonesia, Sri Lanka, and the Philippines express concern over its spread. In Malaysia, authorities incentivized the capture of thousands of kilograms from rivers. In the US, related species have established populations in Texas and Florida, likely due to releases by aquarists.
Questions people ask about Hypostomus plecostomus
What does Hypostomus plecostomus eat?
It is an omnivore that feeds on algae, aquatic plants, small crustaceans, and snails. Its sucker-like mouth allows it to adhere to surfaces while rasping food.
How big do these fish get?
They can reach a maximum standard length of 50 cm in the wild. In captivity, they typically grow to about 38 cm due to environmental constraints.
Is it safe to release into local waters?
No. It is considered invasive in many regions including the US, Malaysia, and the Philippines. Releasing it harms local ecosystems and may be banned.
Why is it called a pleco?
Pleco is a shortened version of plecostomus. This name comes from Greek words meaning under-mouth and folded, referring to its unique mouth structure.
Good reading and sources
- Hypostomus plecostomus on WikipediaEncyclopedia
- More photos on Wikimedia CommonsPhotos
- Wikidata recordOpen data
The facts on this page come from the Wikipedia article "Hypostomus plecostomus", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.
It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.
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