If you have a sucker fish does it clean your tank?

Plecostomuses, commonly called suckermouth catfishes, plecos and hypostomus cats, are a diverse group of fish including several hundred species. They do eat algae, but they are only one small part of a complete aquarium cleaning regimen. They do not completely clean your tank and require maintenance themselves, they will grow based on the space available and can become very large, outgrowing their tank. The waste they produce adds back into the bioload and water chemistry of the aquarium. Additionally, they can become territorial, aggressive, and damage tank mates over time. A plecostomus is recommended for algae management alongside regular tank cleaning.