I have a 10 gal community tank- 3 Zeb Danios, 3 Harlequin Rhasboras, 3 Black Tetras, 2 algae eaters, a panda cat, and a Honey Gourami
(all fairly small). Recently one of the Zeb Danios, a male by the size, has what appears to be red inflamed gills (at least, that's what it looks like, but of course he won't sit still long enough for me to be sure!). He's eating and swimming normally, and I haven't noticed any other weird stuff going on in the tank. The algae eaters sometimes chase the other fish, but I've never noticed any signs of nipping.
I usually refresh 30-50% of the water every week, adjusting the chemistry as necessary (the local fish shop tested the water and said it was fine).
Any ideas of what I might be dealing with here? Anything for me to check or look for?
Appreciate any suggestions or thoughts.
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