Melafix is an antibacterial remedy for the Koi and Goldfish in your pond. Simply use it when adding new fish to the pond. Melafix helps treat eye cloud, mouth fungus and fin and tail rot. Melafix is an all-natural remedy that rapidly repairs damaged fins, ulcers and open wounds. It's safe for snails and other invertebrates, and it will not harm aquatic plants. Melafix will not affect the pH or the biological filter. When using this product, make sure it is in a well-ventilated area and that you avoid all personal contact. It is also important to prevent concentration in hollows. Contact the pros at PoguePoolSpa.com for more information on this all-natural fish remedy.