Fresh water crocs not being dangerous?
I don't think this is true because of a news story I read a few years back about some touring group in which at least one woman had been devoured by a fresh water crocodile in Austrailia. It appears that tourists had regularly been warned about bathing in waters in the part of Austrailia through which their tour went. It's been a long time back that I read the story, but I believe there was mention of a waterfall in it. 
I'd stay away from crocodiles in general, if I were you, unless you're a Crocodile Dundee type person.