how do you cure fish

[30gal4fish]

if the fish has ich, should i take the fish out and treat him alone, or would this be more strees for the fish and will cause him to die.
another deseas, if my fish has the bacteria to cause him to have bad nutrition or red spots on the skin, what should i do.
are this fish salvable? can they be cure or maintain alive, or the chances for survival are very small?

 

[rainfishy]

If your fish has ich you should read about ich in the information section at the top of this forum. treating it is a very detiled process and you need to educate yourself