For this product we require a completed Drug & Chemical Affidavit on file. If you have not submitted this form to us, please click here, and fax (813-671-8237) or email (fishsupplies@verizon.net) back to us. Thank You. USE: Treatment of bacterial infections, both gram-positive and gram-negative. Fin & Tail Rot, Septicemia, Body Sores, Mouth Rot. DOSAGE: 1/4 teaspoonful per 20 gallons every 24 hours with a 25% water change before each treatment. 250 grams (treats approx. 4000 gal.) This product will not work in water with a pH above 7.5. Info from National fish