I have a decent size Mandarin in one of my quarantine tanks. It's actually in my invert qt and I've let it get good and nasty (hair algae growing all over the place). It was full of munid isopods. He has been in there since the first week of November and has put a hurting on the visible numbers. I plan to stick him in my 75 but I'm not really sure how long I should quarantine him. The tank he is in now is a 20 gallon frag tank. He seems to be healthy with no sign of disease but I don't want to chance it. I'm willing to leave him isolated as I do not want to introduce disease in my disease free display.