Once a month, Irby Hartley gives his scuba gear the once-over.  A life-long diver, he was thrilled when the Tennessee Aquarium came to town.  "I said wow, I would like to be able to do that and not have to to all over the world to do it," laughs Hartley.

As a volunteer, Hartley can keep up his scuba skills, keep down the cost of his hobby and keep Chattanooga's top tourist attraction clean all at the same time.  He and 180 other divers scrub the coral and wipe down the windows while watching out for the danger lurking nearby.  The saltwater tank is filled with several different kinds of sharks.  "They (safety divers) have a pipe, a plastic pipe we call a bump stick that sort of puts up a portable fence and shows them that this is our territory," says Hartley.  "And hopefully they won't come in there and we haven't had any problems, they've learned to respect that."

Actually Irby says the smaller fish are more of a problem.  They are constantly nibbling on the divers and impossible to keep away.  It's just something he's learned over his lifetime.  By the way, did we mention that Irby is 84 years old?  "A lot of them don't know it," he says grinning.  "I don't tell them unless they ask."

But you'd never know it.  The forty-minute workout against the waves helps keep his body in shape even if his mind wanders.  "You do you think about other things just like if you were scrubbing windows at home or scrubbing the floors at home.  You think about whatever's on your mind at the time obviously."