This is from my own experience. I don't quarantine fish/coral/ anything. If you do not quarantine everything that goes into your tank including coral and invertebrates, quarantine the fish is not effective enough. I know this is a very touchy subject I would explain but do not want to derail the thread

. A stated above I use safety stop which is a "quick quarantine method" which all it is is two seperate baths and you dip the fish like you would coral super easy and effective . I find I have very good success ever since using it and you can use the dip for multiple fish at a time. After that I will either get an acclimation box and set the new fish in there if I see there could be an issue if not then I will just dump the fish in. I feed very heavy and that allows me to keep my fish fat and happy. Don't get me wrong I do have ick in my tanks but I manage it allowing my fish to get nutritious meals several times a day. I am able to add new fish and have a low chnace of them showing a disease. I find if you can lessen the stress on the fish the more success you will have. I really hope this helps!