We had a 2 week shutdown at year end, so I came in the 21, 25, 28th - and was going to come in on 31st, but had re-injured a shoulder. I'd done full water changes for all of them during that time - and partials for the boys on the 28th (girls big tank got changed on 28th).
Everyone was doing just fine when I left on the 28th - but I get in to work yesterday (4th) and my greenish-yellow crowntail is on the bottom, fins not clamped, but transparent, and when he swam up, it was with difficulty - and he's bloated.
Promptly changed the water and only put about 2 " in his tank (he's in a regular 2.5 gallon and I've put the heater on the bottom so I can fill them only part way. Also put in a bit of epsom salts and some of the Maracyn plus, but I'm not too hopeful. It was fast. Purple Haze took a long time to get that sluggish.
He is still eating - but that's about it.
How in the world did that happen so fast? Could I have introduced bacteria during the water change? PH has been gone since Mid November, and was never in that tank, so I'd think that no bacteria from him could have been introduced.