Hello everyone, I have 10gal just with 4 guppies I feed them twice a day. Water readings are good, 0 ammonia, 0 nitrate, 0 nitrate, 7.4-7.6 pH, water temp. 75-80 degrees, and I also put aquarium salt. I noticed yesterday one of my female guppy has some kind of spot on her body I'm not quite sure...