Medicated food delivers antibiotics directly to fish without disrupting pond chemistry. Use it deliberately.
Common Options
Romet B (sulfa), Aquaflor (florfenicol), KP series (kanamycin). Prescription required in many regions; vet consultation recommended.
Dosing
Follow package: typically 1% body weight in medicated food daily, for 10 days. Don't shortcut the duration — incomplete courses breed resistance.
Sick Fish Won't Eat
Severely ill koi refuse food. Medicated food works only on willingly-eating fish — use injection or bath for non-feeders.
Cycle Awareness
Medicated food residue passes through fish into water and partially impacts biofilter. Increase water changes during treatment.