We captured this little frog at the river and brought him home in our cooler (dumped of the ice and drinks and filled with fresh river water, of corse.)
We've been feeding him house flies and crickets. We've had to clean his tank once. We refilled it with fresh rain water that we collected from the seats of our camping chairs. (It's amazing how much rain water those seats will hold if we leave them outside during a storm.)
In the photo above, our frog had just eaten a cricket, a cricket that was as long as he is, mind you. He did this by biting him and letting the cricket swim, biting him again and letting him swim... this went on till he'd worn the cricket down and gotten him face to face. That's when he proceeded to swallow the cricket and swallow him some more and swallow him some more and more and more till the whole cricket had disappeared head first down into the frog's body (save the leg you see sticking out the side of his mouth in the photo above.)
The frog isn't chewing. He's just sitting there. From what we read, the juices in his body will digest the cricket for him.
We captured a praying mantis last year. And this year, we brought home a frog. I have to say that no amount of reading or videos on insects or frogs can teach what these animals teach us watching them for a mere thirty seconds every other day. It's awe inspiring.