This fish food contains three antibiotics and is for those hard to treat, stubborn infections. It contains equal parts of Flake Fish Food Medicated with Erythromycin, Nitrofurazone and Tetracycline. We recommend you initially treat with the antibiotic containing just Nitrofurazone. If after one week they are not showing improvement, we recommend that you switch to the Triple Antibiotic Flake. For use with Ornamental Fish only.