prima and meta fix Otherwise known as Metaflex and Pimaflex, neither is truly medicinal but rather holistic herbal remedies. Treats fungal infections and both internal and external bacterial infections. Will not adversely affect the biological filter, alter the pH, or discolor water. Safe for reef aquariums and live plants. For use in fresh or salt water. PimaFix has been formulated to work in combination with MelaFix to enhance effectiveness against fish diseases.