In my experience, there is not too much difference in the care and husbandry of a frogfish and any other reef fish. There are a couple of things that I try and pay attention to:
Frogfish are gluttonous and opportunistic. They will try to eat almost any cohabitant, if not now, at some time in the future. This includes other fishes, many invertebrates, and even conspecifics. So I feel, one per tank with little more than snails as tankmates.
Reef-quality water suits them. 75-78°, 1.025/35ppt, <0.03 PO4, <0.2NO3. And while they want clean water, their metabolites create excess nitrates and phosphates...this is not good for corals. Efficient nutrient removal is called for (good skimmer, bioreactor, regular water changes).
They do not seem to like super turbulent flow levels. Corals like Ecotechs...frogfish less so.
It is helpful if you can get them eating frozen food. It is cheaper and easier than live and you remove the pathogen possibilities of live food.
Buy a species suited to your tank size. 25 gal would suit Antennarius maculatus, A. pictus, A. multiocellatus, A. striatus, A. hispidus, Antennatus nummifer, A. coccineus. There are others that also max out around 4" but they will be hard to find.
Get your Frogfish from a reliable source. 14 day guarantees are nice.
Read the gazillion pages of the frogfish files, google Scott Michaels Anglin Fish and Anthony Calfo's Antennarians - Frogfish.
There is probably more but ...
Oh, and don't feed them goldfish
poor quality pic, but gives you a general idea....
