I'm a fairly experienced hobbyist that hasn't had any aggression deaths in a tank for many years. Recently my 90 gallon tank has been getting wiped out. First some Siamese algae eaters, and then a fantail goldfish. It happens like this....
The fish that is about to die shows little to no effects (except the goldfish which I'll get to later). It acts completely normally, and then a couple HOURS later they start darting around at full speed, very randomly until they seemingly become exhausted, and start floating around being carried by the current in the tank at which point they're practically dead. They die a minute or two later. I've seen it happen to 3 Siamese Algae Eaters over the span of about 2 weeks, and then tonight it happened to a fantail goldfish. I was treating the goldfish for some splotchy, streaky redness with some white spots on it's tail which I believe was some bacteria or a parasite. It was fine when I got home from work, begging at the glass like usual, and then 2 hours later I came back downstairs and it's darting around briefly and then proceeds to go belly up, floating around practically dead. I removed it and put it out of it's misery.
I really don't know what could be causing this. I'm open to any and all suggestions. My parameters are fine, and it's not the tap water since I have a 180g right next to it (with clown loaches which are fairly sensitive) on the same water change schedule. Any ideas?
The fish that is about to die shows little to no effects (except the goldfish which I'll get to later). It acts completely normally, and then a couple HOURS later they start darting around at full speed, very randomly until they seemingly become exhausted, and start floating around being carried by the current in the tank at which point they're practically dead. They die a minute or two later. I've seen it happen to 3 Siamese Algae Eaters over the span of about 2 weeks, and then tonight it happened to a fantail goldfish. I was treating the goldfish for some splotchy, streaky redness with some white spots on it's tail which I believe was some bacteria or a parasite. It was fine when I got home from work, begging at the glass like usual, and then 2 hours later I came back downstairs and it's darting around briefly and then proceeds to go belly up, floating around practically dead. I removed it and put it out of it's misery.
I really don't know what could be causing this. I'm open to any and all suggestions. My parameters are fine, and it's not the tap water since I have a 180g right next to it (with clown loaches which are fairly sensitive) on the same water change schedule. Any ideas?
