It depends what you are treating and what types of wild fish. There isn't anything quite as broad spectrum in parasite treatment as Aquatronics back in the day. If you are dealing with wild caught fish and can't get information on what they have been treated for, you should buy or know where to localy buy praziquental (Hikari Prazipro), levamisole (Prohibit) for internal round worms, Dimilin or Hikari Cyropro for anchor worms or fish lice, metronidazole (New Life Spectrum Hexshield is best and easiest).