Quarantine doesn't mean you need to medicate the livestock with anything, all the tank is for at this stage is to provide a stable environment in which you can observe the newly purchased creature or coral for at least 2 weeks.
If in that time no problems with the livestock arise then you can add the stock to the aquarium with peace of mind knowing you have made steps towards a problem free marine aquarium.
Should a problem come up then you treat it accordingly in what would now become a hospital tank.
A hospital tank would typically undergo a number of changes such as the water parameters like salinity, temperature, be medicated with things like copper sulphate, anitifungal or antiparasitic drugs.
What changes are made or what medications are added will of course depend entirely on what problem is being treated.
There are ways to set one up in a cost effective manner that will allow you to observe newly purchased livestock and ensure it is healthy before adding it to the display system.
You will need to add a start up culture of live nitrifying bacteria to "seed" the QT and sponge filter to avoid deadly spikes in ammonia.
Treat this tank as a regular marine tank in terms of cycle times.
Things you will/may need:
Should you see any issues with the live stock in QT then don't hesitate to ask a question on the Marine Aquarium Fanatics Australia Facebook group for advice on the best treatment..
Information provided by:
MARINE AQUARIUM FANATICS AUSTRALIA