High Ammonia in QT = not good

[kwirky]

I've quarantined fish in hyposaline conditions before (1.016 salinity). That's another option. Much safer than medication and no worry about killing off biological filtraiton. You can bring salinity down from 1.023 to 1.016 in 12 hours but to bring it back up to 1.023 you have to spend 3-4 days.