Originally Posted by lost_snow
I was researching and Mardel makes Trisulfa, anyone used it? it says that its safe and copper free. If my tank already had ich then why would none of my other fish have it?
Fish can fight off ich if they have a healthy immune system. The problem is that ich will still host and breed. You may not notice it on the fish, but if ich is in the tank with hosts then it is breeding. They will infest the weakest first, but any of the fish can be carrying the parasite. There are many medications out there claiming to kill ich, there are only two proven methods that actually work; Copper and hyposalinity. Do not add medication to your display. Even if you have no LR, LS, or snails and inverts of any kind. You will ruin your tank for future inverts. Please remember that ich IS an invert. Nothing that kills ich is safe with any other invert.