I have recently started a QT for that exact reason. I would never want to infect my other fish or have to tear apart my tank to get it out. I picked up a 20 gallon tank for free, and i bought a HOB
aqua clear filter for $10 used. Put a $10 used maxi jet 1200 in there with a heater and let it cycle with a mini piece of LR
in the filter. After two- three weeks it is ready. I also coral dip all my corals as well. Not in the QT tank but in a smaller container.
I keep my new fish for about 2 weeks in the QT tank. Gave them some ceramic pots to hide in.