API MELAFIX fish remedy heals bacterial infections such as fin & tail rot, eye cloud, pop eye, body slime, and mouth fungus. As a general note, all API fish remedies can be used in conjunction with each other safely, as long as you are able to follow the directions for both during treatment. We would not recommend using more than two fish remedies at a time unless you are certain of the diagnosis of multiple ailments so that you can tell which fish remedies are working or not working while troubleshooting a stubborn symptom or disease.