About a month ago we bought 2 corydoras one had lighter patch on the top of his body in front of his dorsal fin over time it got whiter and a little larger. Today looked in and not it has opened up and looks like as if another fish took a chunk out of him . I have seen this same type of "hole" in a fish in a sick fish tank at the the store but never knew what it was Does anyone have any ideas
All water tests are fine .
All water tests are fine .
