I suggest the most somple approach first. Sa;t will increase your conductivity if you add it to the tank. Salt does NOT evaporate. I have used PIMAFIX for years and have NEVER had a problem. It is an all natural preparation. Remove the fisg from the tank and give a simple bath and return. Everyone has different opinions. The old timers have one set of standards that have worked for them, and still others have methods that may be different, but still just as effective. Not an argument....just advice based on a person's experiences. Warmer water kills ich as well as other pathogens incliding certain bacteria. Aerobic bacteria need air! The best thing in my opinion is a hospital tank for your sick fish until he starts to show improvement. As you mentioned you have a cycling tank. Sickness and disease in a cycling tank is a water quality problem ALWAYS unless the fish was already sick when you put it in the tank. Through stress, what was not a problem becomes a problem as the immunity of the fish is reduced. Water changes are your best bet. Just be sure to always wash your hands as a form of infection control, as well as making sure your equipment (buckets, hoses, nets etc are clean and sterilized). I have raised Discus for quite sometime, and keeping things simple has always worked for me.
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