There are different types of Aquarium Medication mainly to treat bacteria, parasites, fungus and also to prevent further infections in the fish. Some of the most common medications are like Methylene Blue, Potassium Permanganate, Malachite Green, Fluke Tabs and Formalin. Most of these chemicals especially Malachite Green can be harmful if there’s prolonged exposure and thus, always use according to the recommended dosage and with extreme precaution.
Among the basic aquarium medication mentioned here, two of the most common, which I normally use are Methylene Blue and Potassium Permanganate. Both chemicals are widely applied as antifungal remedy especially to treat some common fungus infection including mouth and fin rot disease. These two chemicals also do not leave harmful effects that could endanger the fish or human skin in contact, thus would be deemed safe and recommended for general usage. Usually a good practice when using aquarium medication is to remove all the aquarium plants and decoration before applying the solution.

Another important thing, which you should always keep in mind, is that whenever handling aquarium medications, one should take precautionary measures to wear glove so that it will not stain the skin. Malachite Green especially those that contains zinc in the formulary, although will easily kill most parasites and bacteria can be hazardous when it comes into contact with the skin.