Treatment as I do it, and as recommended by JoAnn Burke -
1. day - salt dip your sick fish with a salt bath of 1/2 cup rock/aquarium/solar salt (not epsom salt) per gallon of water, to knock off quite a few parasites. Not longer than 5 min, take the fish out as soon as he keeps floating on the surface without diving down again.
Then put him in a hospital tank, and add 1 drop of QuickCure per gl of water. Have some tank water in a bucket, just in case your fish shows any negative effects from the QuickCure (which mine never had). Then, after 15 min of observing your fish, shut the tank light off or cover your tank with a towel if sunlight touches the tank.
2. day - do a 30% water change and turn your tank light on again.
3. day - add 1 drop of QuickCure/gl of water to your hospital tank, an follow the same procedures as on day 1.
4. day - do a 30 % water change
5. and final day - add 1 drop of QuickCure/gl of water, and follow the same procedures as on day 1.
Nice water change on day 6!
On the bottle of QuickCure is recommended to use it daily, but I have found that its just as effective with using it any other day, and do a water change in between.
You are not overloading your tank with the medication, since QuickCure loses its effect once exposed to light.
Toshi, my big redcap oranda, was VERY infested with Ich after she arrived at my house after a 36 hour trip from China. Its hard to see Ich on a white fish, but she was covered! After a week, all gone!