How to Keep a Pleco: Detailed Guide to Water Quality, Feeding and Tank Mates

The pleco (armored catfish) is a common ornamental catfish, named for its fondness for eating algae on tank walls and leftover food in the aquarium, and is also often called the sucker fish or garbage fish. Its mouth is shaped like a suction cup, its body is mostly covered with bony plates, and it likes to cling to tank walls, rocks or driftwood. Many fish keepers raise it as a tool fish to help clean the aquarium.

The key to keeping a pleco is maintaining stable water quality. It is fairly adaptable and prefers soft water that is slightly acidic to neutral, with the water temperature kept in the low twenties (degrees Celsius); the temperature difference during water changes should not be too large, so as not to stress the fish. It is best to place driftwood and rocks in the tank or leave hiding spaces; with moderate water flow and good filtration, the fish will be in better condition.

When it comes to feeding, you cannot rely on it to clean up by itself. Although it will lick up algae and leftover food, you still need to regularly feed it sinking pellets and algae wafers, occasionally supplemented with blanched spinach, cucumber slices and the like, so that its nutrition keeps up. The pleco is distinctly nocturnal and more active after the lights are turned off, so you can give it an extra feeding before lights-out; be sure to promptly remove leftover scraps to prevent fouling the water.

Tank mates depend on what you pair it with. It is mild-tempered and can generally share a tank with mid- to upper-level fish of similar size and faster swimming speed, but it is not recommended to keep it long-term with slow-moving fish that have abundant body slime, such as goldfish, because the pleco may suck and scrape against their bodies and cause injury. Adults are not small, so the tank must have enough space and the stocking density should not be too high.

The pleco has a long lifespan and, kept well, can stay with you for many years. Watch daily for abnormalities such as white spots or ulceration on the body surface, and stick to regular water changes and feeding, and it will serve as a stable cleaning helper in the aquarium for a long time.