In saltwater, fish drink constantly and rarely urinate. In fresh water, fish rarely drink and urinate constantly.    

Some fish make sounds by grating their teeth and others, like some catfish, make sounds from their air-filled swim bladder.

October 23, 2011 | Categories: From the Gremlin

Some fish make sounds by grating their teeth and others, like some catfish, make sounds from their air-filled swim bladder.