begging for answers here. Less than 6 months into this so not very knowledgeable on disease treatment. Added two new fish to my tank (didn’t know about qt will do from now on) and one of them brought in ich. Threadfin now died from it, tuskfish is not doing well. (Camera will not pick up the spots but it looks 100% textbook ich) LFS is taking them both back for a return, but now what do I do going forward? FOWLR tank with 2 clownfish, a royal gramma, fire fish goby, blotched foxface). None of them appear to have it, but from what I understand it is still in the tank/will always be in the tank? How do I/can I completely eliminate ich so I don’t have to worry about it infecting my fish in the future? TIA