Plecostomus (often called Plecos or "Cleaner Fish") are armored freshwater catfish famous for their specialized sucker-mouths, which they use to cling to surfaces and scrape away algae.
Role: Excellent bottom-scavengers that eat soft green algae from glass, rocks, driftwood, and decor.
 Size: Common Plecos can grow massive (12–24 inches / 30–60 cm), though smaller dwarf species like Bristlenose Plecos stay under 5 inches (12 cm).
 Behavior: Mostly nocturnal, peaceful, and slow-moving bottom dwellers that prefer hiding in caves during the day.
 Care Needs: Require real driftwood in the tank (essential for their digestion), warm water (72–80°F / 22–27°C), and supplemental feeding like sinking algae wafers or fresh veggies (cucumber/zucchini) as they cannot survive on glass algae alone.