Many hobbyists keep scavengers specifically to manage algae and leftovers in their tanks or ponds.
: Often called the "janitor fish," these armored catfish use sucker-shaped mouths to graze on algae and debris. Scavenger Fish Names
In the wild, scavengers are vital for clearing away carcasses and maintaining the "health" of the seafloor or riverbeds. Many hobbyists keep scavengers specifically to manage algae