When your fish is infected with ich, you have two choices. You can either use medication
(not very pleasant) or use "salt and temperature" method. The latter works surprisingly
well and experienced aquarium hobbyists have been using this method successfully for years.
These are the steps that needs to be followed:
Add some sea salt - make sure you use salt that is aquarium safe. Don't use marine salt
or cichlid salt. 2-3 table spoon per 5 gallons of water is sufficient. You need to add
them slowly - 1/2 tablespoon per day would work.
Raise temperature to 86F (30C) - Make sure the target temperature is above 85F otherwise
this will not work. The temperature should be raised slowly - few degree per hour at the
most. At higher temperature, water cannot hold as much oxygen, hence water surface
agitation will need to be increased. One way to do this is to lower your tank water level
by 1 inch or so, if you have a HOB filter. This will cause water to fall harder into the
surface hence more disturbance is created. If you have a power head, position them so that
they will create more splash. This will provide better gas exchanges at the surface,
providing improved opportunities to absorb more oxygen from the air.
Wait for 10 days - or 3 days after all symptoms of ich are gone from all fishes in your
tank. Once cured, you should do a 50% water change.
There are few strains of ich that survives temperatures as high as 95F. If you are unlucky enough
to have this in your tank, you have no choice but to use the medication. But for most cases,
high temperature method works well and is less destructive compare to the medication method.
You can further discuss or leave suggestions in this forum.