Check the listing for details. Fritz Maracyn - 10 Count- Free US Shipping. Condition: New. Listed at 15.99 USD. About Fritz Maracyn Provides relief from bacterial infections such as body fungus, gill disease and popeye in fresh and saltwater aquariums. Fritz Maracyn is a specially compounded broad-spectrum antibiotic (erythromycin) which has been shown to be effective against a number of pathogenic bacteria associated with ornamental fish disease. It was developed for complete but gradual dissolution in water. It is primarily effective against gram-positive pathogenic organisms. Symptoms of clamped fins, swollen eyes, heavy or rapid breathing, patchy coloration, change in swimming behavior or corner-hiding can be signs of possible bacterial infection. All suspected bacterial infections should be treated immediately. Fritz Maracyn is non-toxic to invertebrates. Follow dosage directions as detailed on the product packaging. Check out my other listings for more Bashsea Products, Clear Mesh Netting, BSI Super Glue, DR Instruments Fragging Tools, and Rotifer Mesh Free shipping to the US