Originally Posted by Bearchumjs
That's how I treated my tank for Ich when my feather fin catfish (a new addition at the time) had Ich. It worked great and I haven't seen any Ich since.
It really does work. The only potential problem I've read about is if your water quality is not great, or if the fish has been severely nipped, or combination of those. Apparently that can lead to an increased risk of columnaris. But if your water is good and the fish are otherwise fine, it's a great treatment.