Random Clown Killie Death?
My tank has been running for about half a year now, and I added new fish after the previous occupant died. It had about five clown killies. Two days ago I left for a day trip, and when I came back yesterday I noticed one of the killies floating at the top of the tank, fins clamped, discoloured, non-reactive, and not really swimming around, and it died the same day.
Checked my water parameters and my ammonia was in between .25 and .50 ppm. I changed the water the same day and removed the source of ammonia (a cucumber I'd left too long and a shrimp that had died in a hidden place), but he still died. I'd suspect ammonia poisoning, but it seems that none of the other fish were affected at all, and I didn't see any red streaking or external problems other than lethargy and a loss in appetite.
Any ideas? Could this possibly affect my other fish (they're all eating, swimming)? Thanks!