Looking for peoples opinion on ich and if anyone is living with ich how is it going do your fish get immune to it? My tank has been ich free for a while now but recently I added a blonde naso tang and a purple tang to my 220 gallon display tank. I also qt my fish prior to putting them in my tank. I’ve had to pull all my fish out for 72 days to get rid of ich before and my tank has been doing great until I added my purple and blonde naso. The next morning I noticed my purple had a couple white spots on him amd I didn’t know how he could possibly have ich after doing my qt which ever only recommends and doing your best to keep an “ich free” tank and then over night ich is back in the tank. I guess I just don’t know if pulling the fish out is really going to solve anything or not if one fish can get it over night after being qt then what’s the point I guess. Just looking for other people experience with this and maybe opinions on what I should do. All of my fish are eating very well and don’t seem bothered by the ich that’s there I’ve been watching it and the only one I can see that has it is my purple tang there are some more spots then the other day but he still seems happy and eating very well. I do have a qt tank set up if I need to remove them.