I'm hoping that someone will have an idea what happened to my fish. . .
I cycled a 20 gal long tank. I did a fishless cycle with pure ammonia. I also planted the tank. After the tank finally cycled and the ammonia was at 0 for 2 days, I added fish (5 glowlight tetra last monday).
All the fish did very well their first week in the tank. 4 would swim together. One fish (dubbed "the loner fish") liked to hang by itself.
I was planning on adding more fish tomorrow to my tank. However, last night, the loner fish wouldn't eat. I tried to get it to, but it wouldn't. It also didn't swim too much and appeared to be breathing rapidly. This morning it acted fine. Tonight, I found it dead at the back of the tank. It was really bloated
Does anyone know what might have happened to it? I'm concerned for my other four fish. The appear to be fine, but I don't want them to catch whatever the loner fish had. I also don't want to introduce any other fish into the tank until I'm sure no others will get sick.
The loner fish appeared fine: good size, nice coloring, good appetite until last night.
My water params are:
Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate: 3 ppm
Hardness: 13 dH
Temperature: 78 F.
I fertilize the plants in the tank twice a week with Nutrafin PlantGro.
Does anyone know what caused my fish to die? How long will it take before I know my other fish aren't infected? My fish is still under Petsmart warranty, but I don't want to replace it until I know my tank is safe. Thanks!