freshwater fish urine – Why do fishes of fresh water secrete hypotonic urine?
Osmoregulation in marine and freshwater bony fishes: a comparison.

through its skin and gills freshwater fishes do not drink water and
osmoregulation | biology | Encyclopedia Britannica

Here’s a Helpful Reminder Diagram

Austin’s BioBlog: Osmoregulation in Freshwater Fish

within fish the kidney is located towards the very middle of the fish

freshwater fish. Freshwater fish do not drink water, but excrete large

Movement of water and ions in freshwater fish

osmoregulation freshwater.html 44 03OsmoregulationB

Why do fishes of fresh water secrete hypotonic urine?