You have probably seen a kind of fish that clings to the side of the aquarium with a suckermouth. For the most part, these fish belong to the Loricariidae family.
What is a sucker fish?
Members of the Loricariidae family may sometimes be referred to as sucker fish, suckermouth catfish, or armored catfish. Currently, there are close to 100 different genera of these fish and over 680 defined species. Some sucker fish are categorized under an ‘L-number’ naming system because their true taxonomic description has not yet been determined and/or accepted.
Members of Loricariidae can usually be identified by their flatted, bony body and signature suckermouth on their underside. They can come in a variety of colors and seem to make an attractive addition to many freshwater tanks, though their large size and demanding appetite make them more difficult to successfully keep.
Some of the most common species to come across in the aquarium trade are the common pleco (Hypostomus plecostomus), the royal pleco (Panaque nigrolineatus), and the bristlenose pleco (Ancistrus sp.).
How big do sucker fish get?
Sucker fish are notorious for their ability to quickly outgrow a tank, despite their slow growth rate. Species of Loricariidae can range from under an inch (2.5 cm) in size to a massive 39 inches (100 cm) long.
Because of their large size, most species are not kept in typical freshwater tank setups, and many need to be transferred to ponds as they grow.
What do sucker fish eat?
Sucker fish are largely omnivorous, with some related species even relying on wood for supplemental food. These fish live on the bottom of the substrate and use their suckers to scrape algae and biofilm off of surfaces. However, they may also use these suckers to tear the meat off decaying fish and other invertebrates.
While these fish aren’t usually aggressive in the tank, they won’t hesitate to eat when they find food; these fish have a very good sense of smell and heightened taste buds so following scents as they carry through the water is usually not a problem for them!
How long do sucker fish live?
Sucker fish can live for a long time in optimal tank and water conditions. Some related species have been reported to live over a decade, and can sometimes even get close to the 20-year mark.
Unfortunately, there is a lot of incorrect information about sucker fish. They are often sold as mainly algae eaters that stay under 5 inches (12.7 cm) when fully grown. This is not correct, and each Loricariidae has its own requirements and tank preferences.
Always make sure to research the type of fish or invertebrate that you plan on adding to your tank to ensure that it’s a perfect fit!