The Atlantic Blues are definitely not. and I don’t think I want to go with another tang anyhow. Surely there are some types of fish that are more resistant. I’m thinking now it’s not a matter of choice for me, but more of what can be considered an option. <... Mmm, please do see the list (of families of fishes) listed in particular at the Cryptocaryon area... these are the more sensitive/potential carriers, "hard to cures"... at the other end of the spectrum...Triggers are tough, basses by and large...> I’m currently in the process of skimming out the Quinine and doing some partials. After a week or so I’m going to reintroduce my QT’d live rock and stars, snails, hermits, pods, etc. After a week or so of observation, I will have the 20 gallon available for a QT tank. I do not know, though, if I have eliminated the ick because I removed the fish that could not resist it (while continuing the treatment) or