I have been struggling with this stuff the last few weeks as well and I think your comments above are very important. When you try something you have to give it time to work or at least time to see if it will work. If you are changing things every day or every other day you arent going to see much of anything but stress and possibly you will make more problems for the tank.
For me this stuff likes my giant hygro and my swords - thus far all I have done is spot treat with excel which seemed to knock some of it out. I'm going to keep that up for at least a week or two before I try something else - that is unless it starts to get worse.
