Ok, my thoughts on treating ich (like anyone cares
) If a fish gets ich it's mostly likely due to stress of one sort or another. Trying to catch said fish and put it in a hospital tank is going to do nothing good for the stress level. This is assuming a reef tank with lots of places to hide and snag nets, etc.
One needs to accurately/honestly assess the cause of said stress and alleviate it immediately.
Now, a healthy well fed fish is going to be better able to fight off the stress and therefore the disease/parasite/nasty things better.
So, if it were me, as soon as I see any outbreak of bad in my tank, I feed a higher protien diet (PE mysis is my favorite) as well as soaking nori in freshly squeezed garlic oil. You do this by crushing fresh garlic and rubbing the nori through the pulp until it's soaked (this is where the soaked part comes in). Feed as much as the fish will eat until it appears bored of eating nd remove leftover nori so it doesn't pollute tank.
Now *IF* the fish is already in a bare tank, then go ahead with hyposalinity/copper/voodoo, whatever works and is recommended by the masses. I've never gone that route, but haven't had lots of need to treat fish. Just my 2 cents, yes, Rob, I know you think I'm nuts.