I have a medium planted 55 gallon, with 3 guppies, 1 pleco, 2 ghost shrimp, 1 apple snail, and 5 yo yo loaches. I want to add a few mollies and possibly some cat corrys. I was also thinking about 3 dwarf frogs. I this OK?
It's ok in terms of stocking levels (although the pleco could be a problem depending on what type it is). The biggest problem you'd have with the ADF's (make sure you get ADF's and not African clawed frogs!)is feeding them as they are not aggressive eaters and the yoyo loaches, guppies and, when you add them, the corys would probably gobble up all their food before they even started to move towards it. You may end up needing to hand feed them.
Oh, and they don't like tall tanks because they aren't good swimmers and need to rise to the surface regularly for air.