First of all, raising the temp will not kill that Marine Ich it works for freshwater.
Second if you want to treat the fish with copper you need to get them out and into a hospital tank.
You can try Dr G's parasitic food, (i am actually feeding that to my personal tank right now). It was recommended by someone that I trust.
Now here is the cavaet to it all. Unless you plan on qt'ing everything, even coral then you may never beat Ich. I have personally decided that it is part of nature and very hard to get rid of permanantely. Even one spore of ICH that is on a piece of coral may spread into hundreds. So the only way to really make sure that you are ok is to have a frag tank and qt the coral for at least 12 weeks IMO. But the prob is that you cannot add anything to that tank while they are in there.
I am sure that people may disagree but Ich is probably in all tank since most people do not properly treat/qt fish before introducing them into their DT.
I would give Dr G's food a shot.
Yours may have but most don't. The decision to basically do nothing isn't really a good thing. Most of the time people will lost the majority of their fish by not acting. And I mean by doing nothing is either doing nothing or treating with things like cleaner shrimp, neon gobies, garlic and such which is basically doing nothing as none of these things will get rid of the ich from the fish or from the tank itself.If they are in a reef tank and the fish are eating and active then just keep them eating and they will beat the ich. Mine did.You never know if your qt process will work and if you are lucky enough to get your fish out of a reef tank you will need another system to house them for 8 weeks minimum and treat them with copper. You will never be able to use this for coral after the copper treatment.
I used a varied diet with some neon gobies and cleaner shrimp.
And everyone was fine after a few days.