What is this patch/lump on normans lampeye killifish?
Has been there for a weeks. Tested water (liquid test) and no issues but I did upgrade filter a few weeks ago (seemed to go well - swapped media and tested regularly). I tried treating the tank with esha 2000 but it hasn't gone away. Fish is still very active and eating. No other fish have it.
u/Ornery-Cheetah-7549 — 3 months ago