Still going on. They're breeding at a rate that's keeping up numbers, but they're still dying with exactly the same symptoms every time. There's definitely some disease specific to this species (possibly related species as well, but I've not seen evidence either way.)
Every Columbian I keep...
Very bad idea. Part of the treatment for ick is to raise temperature. Guess what that does to bacterial infections (which, incidentally, your description sounds rather more like)...
Sounds like the definition of a scam to me. "You must add this stuff; your fish really need it" when actually it does naff all for them most of the time.
It's a bit more than "not the same strain"; they're a completely different organism. For FW you also increased temperature and added salt so why do you ascribe the success to the garlic specifically?
They always result in either floating at the top or being stuck at the bottom. That is what swim bladders do; they maintain the fish's bouyancy. Keeling over like this can have lots of causes, so I don't know why you'd want to blame the swim bladder when the most obvious symptoms of swim...
Salt doesn't change the pH. Chloride combats nitrite toxicity by competing for takeup at the gills. Not sure of the relevance there.
The paper mentions that there were pH differences but gives not indication of the magnitude of these differences.
He's bang on. You can have levels of 2-3ppm in pH 6 and the fish will be fine, whereas they'll die quite quickly at 0.5ppm at a pH of 8. This is why ammonia readings without pH figures are pretty meaningless as regards toxicity.
Doesn't even need to be stable. pH swings within a point or two do not harm fish, despite widespread belief that they do. Said it before, I'll say it again - I've moved fish from pH 7.6 QT to pH 6.5 peat filtered CO2 injected display tanks by simple temperature equalisation and release. Never...
Raising this thread from the dead - I'm losing Columbians now quite quickly with exactly the same symptoms. None of the other species of fish in the tank are in any way bothered. After having the spots for ages (it's not black spot; the patches are too large and too diffuse) the fish start...