Today I came across this article in Coral the April/May 2008 that was so interesting to read entitled Terminal Feast by Tobias Engel (pg 75). He explained how frogs are ambush hunters that lay and wait for its pray. He had a striated frogfish that was 5 inches long and he ended up placing the frog in a tank with a bamboo shark that was 12.5cm long. He said that he fed the frog 3 fish before he relocated it. He left the tank for 10 minutes to get the bamboo shark some food, and when he came back, he noted the frog was very large with this "tongue" hanging out of his mouth. He was just laying at the bottom of the tank.
He had eaten the shark, and in a matter of 10 minutes he had completely swallowed it. He had pictures of the fish, and you could not even recognize it. It took the fish 3 days to die, and he did a necropsy on it, and pulled out the shark. It had not been effected by the digestive juices of the frog at all, and it only shrank one inch.
Very interesting article if you want to read it.
Engel, Tobia. April/May 2008. A Terminal Feast. Coral 5(2): 75-76