I have a 30 gallon set up that has been going for a little over a year. Things have been going well recently except a few fish have come down with the same symptoms...
First it started with one of my diamond tetras a couple weeks ago. He was swimming funny, doing loops around the tank like he couldn't get a handle on which way was up and which way was down. When I quarantined him he was breathing kind of heavy. No other symptoms.
I thought it was just a random fish death but then on Monday evening I found one of my male guppies dead. I remember him chilling at the top of the tank the night before a bit, but thought nothing of it. Then come yesterday, I saw my other male guppy having swimming difficulty like the tetra had. I quarantined him and he was breathing a bit heavily as well. But no other symptoms. He was still alive this morning, but not looking so well. I have a feeling when I come home from work he'll be gone. Tank specs
Size: 30 gallon
Lighting: single T-8 tube, 24 inches - ZooMed Ultra Sun bulb - lights on for 8-10 hours a day
Filter: Marineland Penguin power filter for up to 50 gallon
Ferts: Flourish Comprehensive - dose twice a week
Water changes: 1/3rd tank every 1 to 2 weeks
Occupants: 4 diamond tetra, 10 neon tetra, 4 female guppies, 3 panda garras and some ghost shrimp
pH: high 8.2
Nitrate: around 10ppm
If anyone can help me out with what's going on, I'd really appreciate it! I'm scared for the rest of my tank. All the other fish seem to be doing great. They're swimming fine and eating like normal. Should I treat for something or just kinda wait and see? Any help would be appreciated!