This poor betta has fin rot. He's had it for weeks but I just figured it out. Can't figure out what the stressor is except maybe the pH which might have been as low as 6.6 but is usually 6.8. (I have been doing weekly water changes and checking ammonia levels.)
One week, though, I overdosed the tank on 0-0-3 fertilizer for the plants. Could this have stressed the fish? (Added the start-up dose instead of the waterchange does.)
Two days ago, just after I figured out he has fin rot, he got this spot on his head. No one knows what it is. He swims quite actively, eats actively, no one seems to pick on him (in with a bushy nose pleco, neon tetras, African dwarf frogs and ghost shrimp in a 23 gallon tank).
Suspiciously, there's also a Neon Tetra we got on Thursday with a strange spot that look only vaguely like this one. He's been acting normally. No one can figure out his spot, either.
I know I should probably set up a hospital tank, but not only is that practically difficult right now, it wouldn't have cycled and I think it would stress out the fish to move them.
I started added Melafix to the tank yesterday, but see no improvement in the fin rot after 24 hours. I am wondering if I should treat with Furan-2, Furanase, Maracyn II, or Pimafix. Maybe it would help with both the fin rot and the mystery spots?
Also, do you think I should try to change the pH?
Thanks for the help!