I have a Hippo/Regal also, showed ich in the first week, treated food with Selcon, and still do, make sure the fish eats well, Skunk Cleaner Shrimp took care of the rest. Ich lasted three days, now ich-free for a month. I agree that most systems contain ich, but a healthy, well fed fish, unstressed, will not get it.
I forgot to mention, I feed New Life Spectrum Marine pellets soaked in Selcon in the morning, I think it's Garlic fortified.