Wels Catfish

Found singly, or in small schools, over well vegetated backwaters, of lakes and rivers, a nocturnal species that forages for food close to the bottom.
They feed nocturnally on fish, invertebrates, and sometimes ducks!
Widespread Asia, Europe

This is the largest freshwater fish can reach in excess of 250cm

Siluridae can often be found in the aquarium trade. The family also includes one of the largest freshwater fish.