They get calcium/d3 from their varied diet in in the wild. Their feeders have a eat a broader range of food and the frogs eat a large amount of different insects, much more than we can offer in captivity.

EDIT- I really like Paul's multi supplements and am considering trying the same thing myself. My frogs have never had any health issues using the Repashy alone, but if it's possible to make their captive diet even better, I don't see anything wrong with giving it a try.

I use this schedule, my red eyes are fed daily, my greys I recently dropped to twice a week feedings.

http://www.frogforum.net/food-feeders-live-frozen-culturing-etc/26121-ca-vitamin-dusting-schedules.html