Plecostomus(Hypostomas plecostomas also Hypostomus punctatus) are also known as suckermouth catfish and sometimes as algae eaters. They are also commonly called plecos. They belong to the family Loricariidae. There are several different species of plecos available. They are from South America.
They are peaceful fish that can be kept in a community tank. You should provide rocks and plants in its tank for hiding places. You should only keep plecos in a large tank. The plecos you typically see for sale at the pet store are juveniles and are usually about 2-3 inches (5-8 cm) in length. In their natural environment they grow quite large - up to 24 inches (60 cm) in length, although they usually don't get quite that large in captivity. In the home aquarium they usually reach a size of approximately 12-13 inches (30.5-33 cm), which means you will still need a large tank to house a plecostomus long term.
There are some smaller species of plecostomus available, such as the clown plecostomus, which reaches a maximum size of about 3-4 inches (7.6-10 cm), and the king tiger plecostomus that reaches an adult size of about 6 inches (15.2 cm).
Plecos are mostly herbivores and earn their keep in aquariums by controlling algae. They are mostly bottom feeders, but you will often see them attached to the aquarium glass with their mouth. They will eat algae off the aquarium glass and other surfaces. They will also eat dried, freeze-dried, and live foods. You should feed them some meaty based foods, but you should also have lots of algae growing in your tank.
They are nocturnal fish and so most of their activity occurs at night. Because they are nocturnal fish you should provide caves in your tank for them to hide in during the day.
They do best at a neutral pH (pH of 7.0) and the water temperature should be between 70-79 degrees Fahrenheit or about 21-26 degrees Celsius.
There are no reports of plecos breeding in captivity. In their natural habitat they breed in pits dug into the substrate. After the eggs have been layed and fertilized, the parents guard the eggs until they hatch. After the fry hatch they feed off of the body mucus of the parents.
Sometimes the eggs of plecos are collected from riverbanks and then hatched and raised on fish farms. Most plecos that are for sale in pet stores are derived this way.