A follow up question to my fish having ich. I currently have lake Michigan water coming to my house. My friend told me it could be the reason my fish got ich. So I was wondering if it were possible to have a fish store test my water to confirm if it's safe or not? The reason I ask is because I need to do water changes frequently because I have goldfish and I can't have the carbon filter running when I have cupramine treatment in the 30 gall.