ICH CAN CAUSE THE FISH's DEATH! Did no one say this yet?
best removes with copper sulfate meds imo,
it is bad for the fish and bad for everything in general.
From what I undersstand of the bacteria (ich is a bacteria, right?)
raising water temp dosen't kill ich, in fact what it does is speed up the organisms' life cycle so that there's a chance the fish will get over it quicker. I'd imagine it could die if you boiled it, but of course that would kill the fish too.
imo best killed with weak antibiotic poisions, i use copper sulfate. the trick is to get just enough to kill the ich, this much won't usually harm fish. it is wise to take saftey precautions though (such as hosbpital tank)