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 what it is. Need your help... I also noticed that she lose her appetite I am not quite sure what/how to treat her with(what medicine I should get?)I placed her in a hospital tank for further monitoring plz help. I dont want to lose her she is my only pregnant guppy 
