One of my hasbrosus corys has a red splotchy thing that looks to be internal. I don't know what caused it. It seemed to be acting more or less normal when I first observed it but now it is hiding.
using test strips: ammonia 0, nitrite 0, nitrate less than 10, ph around 7.2,
temp 76 F. No inhabitants that could have really wounded it I think, just other hasbrosus, CPDs, chili rasboras, ottocinclus, and some cherry shrimp and snails.
I've had these guys for over a month now. No signs of problems in any of them up until now.
All the others are looking/acting completely normal. Is this something I should be worried about spreading? Do I need to treat the fish and if so how? I don't want to stress it too much.