The one in my city has closed down now, but a few years ago, my mum and I went to a place called 'The Australian Shark and Ray Centre'. There were a small number of pools filled mostly with sharks but one had a couple of large rays. Basically, visitors could hire a wetsuit, purchase cups of prawns then go in the pools and hand-feed the sharks and rays. We were the only visitors on that particular day, so we had the whole place to ourselves and the friendly staff even allowed us into the pool with 'Gigantor', a 3-metre Tawny Nurse shark (though we weren't allowed to feed him).
The traditional greeting of Dinotopia: "Breathe Deep, Seek Peace"