how do you know whether to treat or not

[Dorado13]

I just added some fish to my quarantine tank and my fish don't appear to have ich, so I'm not sure whether I should use hyposalinity or not. I have heard a lot of people say to not treat unless the fish have ich because it is very stressful, but how do you know that they don't have ich in there gills or something? Is it possible for a fish to have ich for the 6 weeks in quarantine, but not show it? Or is it safe to assume that if you don't see any signs of ich after the 6 weeks, then they don't have it?

 

[Jerry W]

IME, 6 weeks would be more than enough time to observe a fish for illness. Hyposalinity is not necessary during initial quarantine, unless you see symptoms of crypto. Watch the fish and get it feeding on different foods. Allow it to settle a bit. If all is well, the fish can be added to your display after 4 weeks, or carry it a bit further if you want and go 5-6.