This is what worked for me. Here's the instructions from the bottle.
"Shake well before using.
To use as a food soak:
Apply Garlic Xtreme directly on dry, frozen or live food and allow to soak. Place 2 drops of Garlic Xtreme per teaspoon of fish food each time you feed. As with any food, do not feed more than can be eaten in a five-minute period. To use directly in aquarium: Add 1 drop per 10 gallons of aquarium water. This method would be used particularly if fish are not eating or if they have visible parasites, wounds, or infections.
Does not require refrigeration or freezing after opening, however refrigerating will prolong useful life.
Garlic is safe for all species of marine and freshwater fish, plants, live corals, and other invertebrates. Because KENT Marine Garlic Xtreme is very strong and fish are extremely sensitive to chemical scents, it is not recommended that you exceed 2 drops per feeding."
After the third day I stopped dosing and did a water change then started over one more time. Anytime I see a fish flash I use it on the food for two feedings. It's been six years with no ICH and I don't quarantine. The trick is catch and treat it early.
Not one shred of evidence supports the notion that life is serious.