There are only two ways to treat ICH that have been proven to work. Garlic, pepper etc. is all anecdotal at best.
The two proven methods are Hyposalinity, and copper. Because of their skin, Tangs don't do well in copper, and you're pretty much left with Hypo if you want to treat him.
Know your enemy, read up, and be prepared to deal with this once, the right way.
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