My thoughts, exactly. In fact, that and similiar practices are creating greater problems than the average and unsuspecting hobbyist realizes. See link below:A single, small, monthly dose, of metronidazole, is worse than doing nothing at all. And that is also exactly how super bugs are created.
Ornamental fish industry faces increasing problems with antibiotic resistance
We don't think individuals should ever use antibiotics in a random, preventive or prophylactic method/QUOTE]