Kuhli Loach (Pangio kuhlii)

Kuhli loaches are built to disappear: an eel-thin, nearly scaleless body that slips into gravel and driftwood gaps most fish couldn't fit a fin into, with barbels doing the navigational work eyes can't in that kind of zero-visibility crevice. That same flexibility is a well-known escape-artist liability — any gap in a lid or filter intake wide enough for a pencil is wide enough for a Kuhli.

Care level: Easy · Temperament: Peaceful, shoaling · Max size: ~4" · Min tank: 20 gal · Diet: Omnivore, sinking pellets/wafers