Why do fish nibble on their skin?

Question

Hello, I just saw my mollys, guppies, and swordtails nibbling on my hand. Does anyone know why?

stowaway · Answer

Maybe they were hungry?

jentolon · Answer

You eat the skin flakes, I'd say. or they worship the holy hand that always gives them something to eat with kisses.

lillyxdxf · Answer

They crumb off the dead skin, which make many fish in free nature even in large fish.

vapo901 · Answer

If they were bigger, they would eat your fingers... But as they are so small, they enjoy minerals and skin scales ^