a) 76°F
b) 6.8pH
c) 1dGH
d) 1dKH
e) 0 Ammonia, 5 Nitrate, 0 Nitrite levels.
f) 30% PWC once-twice weekly
2. Tank set up
a) 29g
b) Sub 1-3" play sand
c) penguin biowheel 200 HOB
d) well planted with swords, wisteria, pennywort, anubias, wendtiis + huge malaysian driftwood
e) 3 male black C schultzei, 5x 1" C sterbai, a 3" genuine SAE, a 2" bristlenose, 3 amano shrimp, 1 stowaway guppy fry, asst snails
f) Set up approx 6mths
3. Symptoms / Problem description
My female black C schultzei has been kinda hiding the last couple of weeks, today she appeared with blotches of paleness above her eyes and spreading back down her sides. My first thought was velvet as it appeared to shine under a flashlight but I think that may be because its light on a black fish. What it actually looks like is as if she is peeling after a bad sunburn, or like a clearcoat bubble on a black car. A strange description but that is exactly what it looks like. It is smooth, like cracked plastic, not fuzzy like fungus nor dusty.
Background: Approx 3 weeks ago my DIY CO2 bottle tipped over and emptied 1 liter of week-old yeast mixture into the tank while I was gone for 2 days. I removed all the plants, washed them off and performed multiple large water changes to clear it out. The biofilter didnt seem affected and there were no immediate fish casualties nor apparent distress. Upon returning from a trip this weekend my single 1" C. Leucomelas was dead with no obvious cause. My sterbai have stopped dancing against the glass (normally their favorite activity) and the bristlenose has had stress coloration on and off for the past week.
If anyone has a suggestion about what might be wrong with my beloved Betty or how to treat her I would love to hear it, (I think Mr. Frank Falcone might block my emails if I ask him any more questions

Thanks
NOTE: The tiny white spots are on the container, not her skin