What you need to understand is that certain species require special layouts and don't play well with other genus/species. If you're going to go the frogfish route you'll need research what he can be with, and what special requirements he has and you'll probably need to do a species tank for him.
When I walk through a huge pet store like ThatFishPlace I know full well that 80% of what they sell I can't buy....I can't buy it because I chose to go with a full reef tank with inverts so I know what is: too territorial, what will eat my cleanup crew, what will eat my corals, what will kick around my rock work and break sh*t, what will crap it all up when it gets too big, what will eat what, etc.
In my two minutes of searching the net I get the impression that Frog fish are: dirty, so they need a lot of cleaning, eat anything they can fit in their mouth so small passive fish are out, can be abused by larger aggressive fish too so you need care there as well.
Good luck.