I just checked in on my fish, and they don't seem to be doing well. One of my three cory's eyes are sunk into his head, and the barbels on the left side of his face have been ripped off. He is laying in one area of the tank, and seems to be breathing quickly. I found my new pleco dead. I've had him for about 1-2 weeks, and he seemed to be doing so well. I'm testing the ammonia right now, but I doubt that will be the issue. It's been one week exactly since the last water change. The tank is fully established. I never go any more than 2 weeks between water changes, usually once a week. I replace a large percentage of the water, and vac the gravel. The tank is fully established, and the only thing new was the pleco. He was only about 2.5 in.
I've been on vacation this week, so I haven't been able to keep an eye on the tank. I usually spend quite a while everyday observing, so I know when something is wrong. I had someone at home feeding them for the 3 days I was away, with no problems. Everything seemed to be doing well when I returned.
What can I do for my poor cory, and what might have caused his sunken eyes? He looks half dead.
Here's a little info on the tank & it's inhabitants:
*28 gallon, 55 gallons worth of filtration, a few live plants.
*2 platys, small angel (about quarter body size), 2 ADFs, small female betta, 3 corys, and until tonight, one pleco.
*temp is around 78
Any info is very appreciated! Thanks.