Some of the fish in my heavily planted tank are showing signs of fin
rot, and a couple of them are 'glancing' off objects in the tank.
Aside from the fin rot, I don't see any external signs of disease (no
white spots, film, or obvious parasites).

The fish in the tank a
Peacock Gudgeon (9)
Fundulopanchax Scheeli (3)
Betta Splendens (1)
Otocinclus Catfish (6)
Leopard Danio (4)

In addition to the fish and plants, I have a half dozen or so ghost
shrimp, and countless snails, mostly MTS.

I've been using Melafix, but I have the impression it's more for
treating the symptoms rather than the cause.

What medication could I try that won't hurt the plants or the inverts?


Thanks in advance.

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