Good point, and the salt isn't a necessity, it can help sometimes, but maybe it's best not to chance it in this case. Incidentally, I've read with iodized (table) salt, the reason not to use it is that it contains anti-caking agents to keep it free running, and those are what can have a detrimental effect. I've also read about people who use it with no problems.
Flashing, TMK, is something that happens because ich infects the gills before anything else; the fish are trying to rid their gills of parasites. The one lying on the bottom may just feel terrible. Fish heavily infested with ich are very sick indeed, and this seems to me like it could just be a reaction to being infected for a while, but as LongTime mentioned it could be that he's coming down with something else after having been weakened by ich. He's still eating, so don't lose hope.
ScottoMacD makes a good suggestion about the Formalin. I hope it works. Keep us posted.
Flashing, TMK, is something that happens because ich infects the gills before anything else; the fish are trying to rid their gills of parasites. The one lying on the bottom may just feel terrible. Fish heavily infested with ich are very sick indeed, and this seems to me like it could just be a reaction to being infected for a while, but as LongTime mentioned it could be that he's coming down with something else after having been weakened by ich. He's still eating, so don't lose hope.
ScottoMacD makes a good suggestion about the Formalin. I hope it works. Keep us posted.
I also hope you never do come up with those methods! You do your best and learn from your mistakes.
the Mom & Pop LFS by my house told me to "Keep a penny in your filter (corner filter with glass wool and charcoal) to stop disease and change 10% of your water every 4 days." And they were kind enough to let me trade in by baby guppies! 
