I used Medic by Poly Lab and it worked great in my 90 Gallon when my Blue Hippo's got it. Never seen a white dot for 8 months after treatment. I put them in my 300 Gallon after the tank was stocked and within days they had ICH again. I have been treating the tank for the last 3 weeks as directed and haven't seen it on them in over two weeks, plus none of my other fish got it. I feed heavy and treat my food with vitamins, selcon and sometimes garlic a few times a week. My fish are pretty fat and healthy which helps in resisting the disease.
Some people say every tank has Ich, others disagree. I think there are different degrees of Ich, some strands may be stronger than others. After treating the hippos for 1 month and not seeing it for 8 months, I was impressed with the product, then I put them in a new tank that is 5 months old and no sign of Ich and a little stress, then it shows up. Go figure. Maybe the Medic helps to keep it from spreading and may knock it out. It was just weird how they were clear for so many months, then it came back, once moved and a little stressed. And the product is reef safe which is a must.