Hi, keenonfish,
Sorry to hear about your troubles and hope your fish will soon be well.
If you're getting ich meds, can you get something with Malachite Green and formaldehyde?
Because the combination is said to be good used against fungus as well as ich - and, speaking as One Who Knows Nothing, I have NEVER heard of ich being grey and fuzzy...
A bit of salt, at the rate of about 1 teaspoon per 5 gallons, would apparently also be useful against both, without impeding the action of the drugs or damaging your fish, although there may be a PH alteration.
I'm using this (half-dosed Quick Cure) combination, after Maracyn 2 failed me, on a betta with what sounds like an identical problem, and, even though I only switched the meds yesterday, he already seems improved, with the spot on his body gone, and the grey fuzz on the ends of his rays, which had been spreading, and spreading up at least one, and getting longer and threadier, appears to have drastically reduced overnight.
I haven't been able to see any on him today, actually, but he does have long extensions and only keeps still in the higher-level planted areas around the sides/back, so there may be bits I haven't yet been able to get a good enough look at, although I've had a fairly good look at the tips, where it started.
So, at least in his case, whatever the problem is, this seems to be helping.
Have you, by any chance, recently introduced any snails from a questionable source, or noticed great numbers abruptly dying?
I introduced Nerites from a chain store into several tanks some time back, and have now had a complete die-off of pond snails (as well as all of the Nerites purchased) in 2 of the tanks, and have been finding many empty snail shells caught on the filter intake in the 3rd...
Sometimes it seems
we're living the nightmare and never the dream
Edit - I do have a good excuse this time for being unable to type, but I'm too tired to remember it...