Pearl Gourami--scales flaking off?

Hi,

It's been a while posting... and as usual, I'm posting when I'm in
trouble...

I have a Pearl Gourami (T. Leeri), that is a little over 1yr old male.
I also have 3 other female gouramis. (i've had 2 of the female for
about 4 years now, and the male/female pair was added about a year
ago.. since I was *supposed* to have a M/F pair, but after a year, it
was obvious that I didn't!)

Anyway, for the past few months (I think. it's been going on for a
while now), the male gourami has been developing what looked like a
white patch under his scale, sort of on this forehead/nose bridge
line... sort of like someone injected milky white fluid under his
scales. the scale looked intact, no puffiness, just that the
coloration under the scale looked pearl-white. the white patch started
small, and then it slowly grew, but the size sort of stabilized for a
while. He's otherwise not acting ill, and I thought may be it's just a
pigmentation thing, so I've been keeping an eye on it, but haven't done
much. He's pretty active during the day, but in the evenings, he
starts hiding out near the bottom of the tank under the plants (I have
a very bushy tank), but he's always been that way, so.... He's also
been collecting plants and gathering them in the corner of the tank, so
i guess he's feeling well enough to "nest".

two days ago, I noticed that the scales around this white patch started
to flake off. I checked the water quality, ammonia zero, nitrite zero,
nitrate between 5-10ppm. pH is kinda low, but that's due to my low
gH/kH (we have very soft water) and high plant density.

Anyway, since I didn' t know what else to do, I did a 50% water change
two days ago and a good gravel vac, and dumped some Spectrogram
antibiotics (wide-spectrum antibiotics) yesterday to prevent any
secondary infection complicating matters for now. I intend to go
through with the standard 3-day Spectrogram treatment unless there's
some contraindications.

looking at the gourami now after the scales started flaking off almost
looks like hole-in-the-head disease at its worst state, but it didn't
seem to start that way from looking at the info on the web. So I'm
trying to figure out what to do. Other fish looks relatively healthy,
although two of my female gourami seems to be developing a cloudy white
spot in the center of the pupil. Not sure if that is related, or not,
but I thought I'd mention it. I dont' know if this is contagious. I
guess I should set up a quarantine tank just in case? (or is it too
late since he's been in this condition for weeks.. well, without the
scales flaking off, of course).

all non-gourami species of the tank seem healthy (if not fat).

tank:
37G, UGF (2 x aquaclear 200 powerheads) + HOT magnum
97F
ammonia, nitrite = 0
nitrate 10ppm
very coarse gravel

other inhabitants:
4 Gouramis (t. leeri)
4 SAE
3-4 zebra loach (there's supposed to be 4, but I usually only see 3)
6-7 chain loach (b. sidthemunki) There's supposed to be 7, but I
usually only see 6
few otocinclus (there's supposed to be around 5, but I rarely see
them.. too much vegetation)
4 amazong sword (bushy, and taking over tank)
1 huge anubias
bunch of java fern colony that is also overtaking the tank...

linda