I have one and it is eating frozen silversides. When I first got it it wouldn't eat frozen food. I added a green chromis to the tank and it now takes frozen food. The frogfish behaviour changed once there was the motion of a swimming fish in the tank with it.
The chromis stays near the top and the frogfish can't swim so is always on the bottom. They have been fine together for a couple months now.
The trick I found with the silversides is to poke the frogfish in the moth with them. It backs away at first, then snaps at it. Works well. I feed it about once a week.
The tank is a shallow open top with clams and SPS. I wanted something that wouldn't jump and the frogfish is perfect.
I got a smaller variety because it is in a 16 gallon tank. It was white when I got it (it was in a white sand tank). After a week it changed to green and grey to match my live rock.
