Disappearing fish--could it be my African Dwarf Frogs?

A few months ago I was given about 18 molly fish. I have been watching the population decrease, and always keep a lookout for remains, or even just sick fish, but have seen nothing. They are down to 9 now. I also have Neon Tetras, Cherry Barbs, African Dwarf Frogs, and snails.

My tank is well taken care of and healthy, never had any problem with aggression at all. All I can think of is the frogs. Could they be eating my fish? (They did eat my fry for sure, I watched them)