Doxycycline is a broad spectrum antibiotic derived from oxytetracycline. When fish are still eating good, these flakes are effective against both gram positive and gram negative bacterial ailments, such as Fin & Tail Rot, Septicemia and Mouth Rot. It can also be used concurrently with Erythromycin to treat forms of Columnaris.
Treatment: Feed daily 10-14 days. May be stopped after 5 days if no improvement is noticed
NOTE: As with any antibiotic, there is a slight risk of affecting the beneficial bacteria. If the cycle wobbles during treatment, begin small, daily water changes.