Do you think it would be harmful if a fish swallowed a maracyn tab? I am careful to wrap the tab in a net and let it dissolve with the net in the water so my fish haven't had a chance to mistake one for food, but I was just wondering. No a clue what's wrong with this one fish but I've seperated him off and put in half a maracyn. Possibly just stress but a general antbiotic won't hurt, a pond mate died of dropsy about a month ago.