Ah, I was told to use garlic when I first started hanging out on this site, my fish had ich. I assumed it was for helping the immune system like it does for humans. I was also told to only use the fresh garlic, that the bottled stuff was worthless. Thanks for explaining that.Garlic is a proven immune boost for humans but I don't think there's any confirmation about it effecting fish in the same way. Is there? It can marginally help to ward off parasites if fresh garlic is used, as well as assist with infections since it has allicin (only viable for a few minutes with freshly minced garlic---which is why bottled garlic is useless).